Zach Johnson shot a third-round 66 on Saturday for the 2007 Masters champion's best round ever in the tournament.

Zach Johnson’s head perked up. He was standing off to the side of the clubhouse and immediately stopped speaking. He thought for a moment and then offered his analysis. Sixty-three rounds at the Masters almost makes you an expert of Augusta National — its greens, its slopes and, apparently, its eruptions.