BETHESDA, Md. -- Steve Marino withdrew from the AT&T National on Wednesday, citing a knee injury.
Brendon Todd will replace him in the field.
Marino underwent surgery to repair a torn meniscus in his right knee last October. He returned at the Sony Open in Hawaii this past January but played just nine holes of the pro-am because his knee swelled up with fluid.
He made two more starts, but the knee never got better and Marino was forced to shut it down because of a bone contusion on the tip of his tibia and femur as well as avascular necrosis, which prevented blood flow to the inured area.
Marino returned at the Memorial tournament presented by Nationwide Insurance earlier this month. He also played a 36-hole U.S. Open qualifier, as well as the U.S. Open and Travelers Championship before withdrawing at Congressional.