Graeme McDowell won the RBC Heritage with a mixed set of irons. (Lecka/Getty Images)

By Jonathan Wall, PGATOUR.COM equipment insider

Using a mixed set of irons on the PGA TOUR is something that rarely registers an eyebrow raise on a week-to-week basis. Last week at the Zurich Classic of New Orleans, 68 players had at least one iron that was different from the rest of their current set, while 25 players had at least two different irons in the bag.

This week at the Wells Fargo Championship, Phil Mickelson was one of the notables in the field who used a mixed set with three Callaway RAZR X MB (4-6) irons and four Callaway X Forged 2013 (7-PW) irons. 

And if you're looking for a recent mixed-set winner, look no further than Graeme McDowell, who won several weeks ago at the RBC Heritage with four different iron models (Cleveland 588 MT (3), Cleveland 588 TT (4), Srixon Z-TX II (5-9) and Cleveland Reg 588 Raw (PW)).

In recent years, players rarely mixed iron sets, choosing instead to drop long irons and incorporate hybrids. But with the return of utility irons like Titleist's 712U and Callaway's X Utility Prototype, hybrids are no longer the only long-iron alternative. 

Cleveland Golf has seen a massive spike this season in mixed sets and utility iron use, thanks in large part to its 588 line. The 588 MT (Mid Trajectory) long irons, the company's game-improvement long irons, have become a bag staple for a number of players this year — along with the 588 TT (Tour Trajectory), which has a lower ball flight -- to the point that Cleveland found itself at the top of the utility iron category the last two weeks at the Zurich Classic and Wells Fargo Championship. 

The craziest part of all? The 588 MT was never designed to be a utility iron. However, that didn't stop a number of players from replacing their current utility irons and hybrids with Cleveland's 588 MT, which has a hollow head design that allows weight to be distributed for a lower, deeper center of gravity.

Aside from McDowell, who used a 588 MT 3-iron and 588 TT 4-iron at the RBC Heritage, Keegan Bradley (Cleveland 588 MT 4-iron), Charlie Beljam (588 MT 2-, 3- and 4-iron) and Jerry Kelly (588 MT 3-iron) are also using mixed sets with at least one of 588 MT.

"I think players like them as a long-iron alternative because they're easy to hit and go forever," said Cleveland Golf PGA TOUR rep Rob Waters. "The additional length and the ability to work the ball are just a few of the reasons we've seen so many staffers put them in the bag."

For more information or to buy Cleveland's 588 MT or TT line, click here.

Hunter Mahan with one of his S56 irons late in 2012. (Redington/Getty Images)

By Jonathan Wall, PGATOUR.COM Equipment Insider

CHARLOTTE, N.C. — The first four months of Hunter Mahan's 2013 season have resembled a roller coaster ride. The five-time PGA TOUR winner started off on a high note, finishing inside the top-20 in five of his first six events, including a runner-up finish at the World Golf Championships-Accenture Match Play Championship.

Since the Shell Houston Open, however, Mahan's struggled to find his game, missing the cut in Houston and at the Masters, while also posting an "MDF" at the RBC Heritage. 

The lack of consistency forced Mahan to make a switch at the Wells Fargo Championship and shelve his PING Anser irons for a set of PING S56 irons. 

The S56 irons were in the bag last season when he won the WGC-Accenture Match Play and Shell Houston Open. 

Mahan had been struggling with his distance control over the past several weeks and felt a switch back to an iron he had success with last season could rectify the problem. 

The Wells Fargo Championship could be the perfect place for Mahan to get back on track. In his last five starts at Quail Hollow Club, he's posted three top-20 finishes (his best a T12 in 2008).

HILTON HEAD ISLAND, S.C. -- Carrying a handful of wedges in his right hand, Roger Cleveland, Callaway's Chief Club Designer, made his way down the range at Harbour Town Golf Links on Monday afternoon, stopping for a couple minutes along the way to chat with players and caddies about his latest creation -- a Callaway prototype wedge called "Mack Daddy 2."

Roger Cleveland shows off the three different grinds of his Callaway Prototype wedge. (Jonathan Wall/PGATOUR.COM)

According to Cleveland, the wedge comes in two lofts (58 and 60 degrees) and three different grinds (S-grind, C-grind and U-grind). The "S-grind" (Standard grind) and U-grind have a bounce of 10 degrees, while the C-grind has a bounce of 14 degrees. 

The wedge also features a textured face that has milling between the scorelines and, as Cleveland noted, grooves that are more aggressive but still conform to USGA groove regulations. 

Colt Knost and defending RBC Heritage champion Carl Pettersson tested the prototype wedge on Monday and both requested 60-degree wedges with the U-grind.

While it's unclear if either player will put the wedge in play this week, the prototype is already in the bag of two former major winners. Cleveland confirmed Phil Mickelson started carrying a 60-degree U-grind several weeks ago, and Ernie Els used one last week at the Masters.

By Jonathan Wall, PGATOUR.COM Equipment Insider

Looking to capitalize on the first major of the year, Cobra announced on Monday that it's going to release 1,800 Masters-edition AMP Cell drivers to select golf retailers on March 15. Each green driver will be marked with a '1 of 1,800' stamp on the sole for authenticity. 

“We are aiming to be the most desirable brand in golf,” said Jose Miraflor, Director of Product Marketing, COBRA. “It’s one of the most exciting times of the golf season and this Limited Edition Driver builds off of that energy. With all of our game changing technology, like MyFly and SmartPad, we are bringing game enjoyment to golfers everywhere, the added desirability of a Limited Edition Driver for the first Major is exciting for our consumers.”

The AMP CELL limited edition – green driver (MAP $399) is available in right handed models with MyFly technology which allows the driver to be adjusted from 8.5-degrees to 11.5-degrees loft settings, including 9.5-degree and 10.5-degree draw settings. It is available in Stiff and Regular flexes and features a Diamana Blue Board Shaft (60g S and R, 55g L and 45.75-inch length).

Sticking with the Masters theme, the limited edition grip, headcover and wrench also match the head of the driver in "Season Opener Green."

Tim Clark used Titleist's new 913F fairway wood at the Sony Open in Hawaii. (Petersen/Getty Images)

By Jonathan Wall, PGATOUR.COM Equipment Editor

Tim Clark kicked off the 2013 season with a strong showing at the Sony Open in Hawaii.

Even though he finished three shots behind winner Russell Henley, the South African posted his second second-place finish in his last six events, dating back to the end of last season.

Clark, who fired a final-round 9-under 63, put Titleist’s new 913F fairway wood (15 degrees) and 712U prototype 4-iron in the bag the bag for the first time, as well as the new ProV1.

Kirk puts Callaway X Forged in the bag: Newly signed Callaway staffer Chris Kirk decided to switch things up for his first tournament of the season. Despite testing out the RAZR X Muscle Back irons during the off-season, Kirk opted to go with the X Forged irons at the Sony Open in Hawaii.

Kirk, who usually prefers blades, noted that, “the sole of these irons is the main reason I’m playing them.” The switch paid off in a big way as Kirk finished T5 for the week with his new irons in the bag.

Sabbatini uses off the rack TaylorMade Ghost Spider S putter at Sony: Rory Sabbatini decided to make a last minute putter change on Thursday morning before his first round of 2013.

Instead of heading for TaylorMade’s Tour Van for another option, Sabbatini decided to pick up a Ghost Spider S from the Pro Shop at Waialae. The new putter helped Sabbatini shoot 5-under 65 on Friday to make the weekend, where he finished T59.

TaylorMade R1 impresses at Sony Open: Less than a week after Dustin Johnson became the first TaylorMade staffer to win with the new R1 driver, 21 staffers showed up at the Sony Open with TaylorMade’s latest driver in the bag.

Among the notables using the R1 for the first time this season at the Sony were Mike Weir, Greg Owen, Boo Weekley and Pat Perez.

Perez actually arrived in Honolulu with concerns about consistent misses to the right with his R1. But following a meeting with TaylorMade’s Tour staff, he realized his face angle was set open with a fade-biased setup.

After adjusting the shot shape weights to more of a draw bias and tuning the face angle sole plate to 2 degrees closed, Perez had his preferred ball flight. He finished the week T9 with the R1 in the bag and averaged 303.5 yards off the tee.

Callaway inks long drive champion Sadlowski: Callaway may want to consider lengthening its driving range. Just days after the company signed Nicolas Colsaerts — considered by many to be one of the longest hitters in golf — to the staff, Callaway went out and inked another bomber in two-time RE/MAX World long drive champion Jamie Sadlowski.

Sadlowski spent time at the Ely Callaway Performance Center testing the new X Hot driver, where he launched shots over the back net with ease. Callaway's Twitter account even tweeted a clip of Sadlowski launching a drive off the property.

Parnevik signs with Cobra Puma Golf: After nearly severing his right, index finger last March in a boating accident, five-time PGA TOUR winner Jesper Parnevik is kicking off his 2013 at the Humana Challenge in partnership with the Clinton Foundation with a new sponsor, after Cobra Puma Golf announced the Swede would be playing Cobra clubs and wearing Puma Golf apparel this season.

According to Cobra Puma Golf, Parnevik will have 12 Cobra clubs in the bag and will sport Puma’s Spring/Summer 2013 collection along with the new Tux Lux golf shoe, part of PUMA Golf’s Lux footwear collection.

Parnevik will play the beginning of 2013 on medical exemption, which gives him 12 events to make $620,087 to retain his PGA TOUR card.

New Cobra clubs in Parnevik’s bag:

Driver: AMP CELL Pro Driver in Silver (7.5 degrees)

3-Wood: AMP CELL Pro Fairway (prototype) in Silver (13 degrees)

Irons: AMP Forged Irons, 3-PW

Wedges: Trusty Rusty in Rust finish (49 and 53 degrees) 

Divots: Odyssey’s new Versa putter picked up two top-10 finishes courtesy of Charles Howell III’s T3 (using a Versa #1 B/W/B) and Perez’s T9 (using a Versa 2-ball). … Charlie Beljan, Jerry Kelly and Steven Bowditch had at least one of Cleveland Golf’s new 588MT game-improvement clubs in play at the Sony. While it may be designed for the everyday player, all three opted to use the club in place of their long irons. … Perez, Rickey Barnes, John Daly and Brian Harman used TaylorMade’s new Lethal golf ball during the week. … Of the 103 players in the field at the Sony that relied on a Titleist Pro V1 or Pro V1x, 62 played the company’s latest version, including top four finishers Tim Clark (Pro V1), Scott Langley (Pro V1x) and Howell III (Pro V1x).

By Jonathan Wall, PGATOUR.COM Equipment Insider

When Bubba Watson and Hunter Mahan step foot on the first tee for the opening round of the Hyundai Tournament of Champions on Friday, they’ll do so with new drivers in the bag. On Wednesday, Ping announced the newest addition to the Ping G-series with the unveiling of its G25 metalwoods and irons line.

The G-series has always been about forgiveness, and the latest offering from Ping is no different. The G25 driver, which is already being used by Mahan and Watson, is Ping’s largest-profile, most forgiving head design yet.

By moving the center of gravity (CG) lower and further back in the club than the previous model, the G20, players will be able to launch the ball higher with less spin thanks to the ultra-thin-crown and body technology and 460cc Ti 8-1-1 head. The lower CG and variable-thickness 6-4 titanium face insert also helps add additional forgiveness to shots hit off-center.

While the driver is geared towards players looking for extra forgiveness, Ping decided to add adjustability to the entry-level club for the first time in the company’s history.

Following the release of the Anser driver last July, Ping’s first adjustable driver, the company opted to add the same Trajectory Tuning Technology to the G25, which lets you fine-tune the height of your trajectory by changing loft before a round to suit the playing conditions, weather, or changes in your swing. The driver comes in four lofts (8.5, 9.5, 10.5 and 12 degrees) and can be adjusted plus or minus one half-degree.

The G25 line also includes fairways woods and hybrids. The fairway wood comes in four lofts (15, 16.5, 18 and 21 degrees) and offers the same low CG for increased forgiveness, especially on shots hit low on the face.

With the G25 hybrids, the noticeable difference is in the head, which no longer looks like a driving iron. Instead the G25 has a wider sole and round shape, giving it the appearance of a typical hybrid. Like the rest of the G25 line, the CG position is lower and farther back in the lower-lofted hybrids and moves slightly forward in the higher lofts to minimize spin and prevent ballooning. The hybrids come in four lofts (17, 20, 23, 27, 31).

Rounding out the new line is the G25 game-improvement iron. Like the rest of the G-series, Ping’s latest iron is incredibly forgiving but comes with one noticeable difference. Unlike the G20, the G25 irons feature thinner, more progressive sole widths, a thinner top line and moderate offset that should appeal to better players.

Ping also repositioned the Custom Tuning Port (CTP), moving it lower behind the face (it now rests behind against the sole of the club). The tweak not only halved the size of the CTP, it also lowered the CG in the irons, thereby allowing players to launch shots higher.

The G25 metalwoods will be available in mid-February. The driver will have an MSRP of $385 and comes with Ping’s TFC 189D graphite shaft. The fairway wood will be available at an MSRP of $255 and comes with Ping’s TFC 189D graphite shaft. The G25 hybrid will be available at an MSRP of $220 and comes with Ping’s TFC 189H graphite shaft.

The G25 irons will also be available in mid-February and will have an MSRP of $97.50 per club with Ping’s CFS steel shaft; $125 per club with graphite shafts.