Phil Mickelson made his only other Texas Open appearance in 1992, so long ago that the event was only his 11th professional start on the PGA Tour.

Lefty is back — to the surprise of two-time Texas Open champion Zach Johnson.

"Phil's playing here?" Johnson asked Wednesday, a day before the start of play. "I had no idea."

Preparing for the Masters, Mickelson was a surprise entry.

When Mickelson skipped the event last year, he said the Greg Norman-designed AT&T Oaks Course at TPC San Antonio was so "windy and tight it's just not conducive to getting ready for Augusta."

He said the same thing Wednesday after he played the course for the first time.

"You can't really unleash drivers like at Augusta," Mickelson said. "The fairways are very generous and plenty wide to hit. But there's a lot of junk if you miss fairways. You don't want to go after one."

Since the Texas Open moved to TPC San Antonio in 2010, the course has built a rough reputation. The stroke average two years ago was 1.989-over-par, which made it fourth-toughest on the PGA Tour. But after Norman oversaw some changes to the course, the stroke average settled to .740-over-par last year when Martin Laird won with a course-record 63.

Mickelson has struggled this season.

"I haven't had the sort of success I've wanted to early in the season," Mickelson said. "I want to get in contention. I want to have competitive rounds and work on proper golf and managing the game. So this is a great opportunity to build some momentum heading into Augusta."

In his last two starts, he missed the cut in the Honda Classic and tied for 16th at Doral in the World Golf Championships-Cadillac Championship.

"Phil's the type of player that it doesn't really matter necessarily how he starts a season," said Jordan Spieth said, who will play in the same group with Mickelson the first two rounds. "One week he may be off, the next week he can win by five shots."

Johnson, the 2008 and 2009 winner, won the Tournament of Champions in January.

Area resident Jimmy Walker has a tour-high three victories this season, winning the Frys.com Open, Sony Open and Pebble Beach National Pro-Am.

The field also includes Matt Kuchar, Ernie Els, Jim Furyk, Billy Horschel, Valspar Championship winner John Senden, Puerto Rico Open winner Chesson Hadley and Ryan Palmer. Hadley and Palmer are the only players without a spot secured in the Masters who still can get in without winning this week. Hadley can get in the top 50 of the world ranking by finishing in the top five and Palmer can get in with a top-three finish.

Jeff Maggert is coming off a victory last week in Mississippi in his first start on the Champions Tour.