Watson turned professional in 2003 and joined the Nationwide Tour where he played until 2005. He claimed his first victory in 2010 at the Travelers Championship beating Corey Pavin and Scott Verplank in a play-off. In the same year he came agonizingly close to winning the PGA Championship at Whistling Straits, losing to Martin Kaymer in a three hole play-off.
In 2011 Watson won twice on the PGA Tour, the first coming at the Farmers Insurance Open where he finished one stroke ahead of runner-up Phil Mickelson and the second in a playoff at the Zurich Classic of New Orleans from Webb Simpson. In 2012 Watson's won his first major championship at the 2012 Masters Championshoip. He began the final round at six-under-par and three strokes off the lead but recorded a final round of 68 (-4), including four consecutive birdies on the back nine, which left him tied tied for the 72-hole lead with fourth-round playing partner, Louis Oosthuizen. In the sudden-death playoff, Oosthuizen and Watson both made par on the uphill 18th hole before Watson played a miraculous recovery shot from deep in the woods on pine straw to save par and win the title. The victory took him to a career-high world ranking of four.
Watson is known for the distance that he hits the ball from the tee and has won the PGA Tour's driving distance statistic on several occasions.