Phil Mickelson finished a 7-under 65 early Friday to move into contention at the rain-delayed Houston Open.

The defending champion completed only three holes Thursday before an afternoon thunderstorm forced the suspension of the first round. Angel Cabrera and Carl Pettersson posted 65s early Thursday to share the overnight lead.

Mickelson resumed his round at daybreak and birdied both par 5s on the front nine. He strung together eight consecutive one-putt greens before two-putting on No. 10. He then sank a 10-footer for birdie on the par-4 12th.

"The greens were immaculate," he said. "If you get it in the surface, you'd feel like you'd make the putts."

Three-time major champion Ernie Els, who must win to qualify for next week's Masters, completed a 2-under 70 on Friday morning.

Tournament director Steve Timms said Thursday's storm dumped 1¼ inches of rain on Redstone. The players enjoyed sunny skies and calm conditions Friday morning, though Mickelson said the balls were picking up mud when they hit the fairways.

Officials were allowing players to lift, clean and place their balls in the second round.

Mickelson said a bit of mud on his ball caused an errant approach shot to the par-5 13th, leading to his only bogey of his first round.

"There's not much you can do about that," Mickelson said.

Mickelson played with Fred Couples, who won on the Champions Tour last week. Couples, who played at the University of Houston and has made 18 consecutive cuts at the event, shot a 5-under 67.

Ricky Barnes and Houston resident Jeff Maggert completed 66s Thursday. Greg Owen and John Huh each finished 66s Friday morning. Defending PGA champion Keegan Bradley and 2010 British Open champion Louis Oosthuizen joined Couples in the group at 5 under.

Mickelson birdied the par-5 15th, then holed a pitch from behind the 16th green. He was to start his second round an hour after finishing his first, and didn't mind the long day ahead.

"I like being able to come out and play a lot of holes in one day," Mickelson said. "If you start playing well, you get a good rhythm, you can make a lot of birdies, especially out here."

Mickelson says he's prefers playing a tournament the week before a major to get into a "competitive frame of mind." He shot 63-65 over the weekend last year to win by three strokes over Chris Kirk and Scott Verplank.

The Houston Open became the run-up event to the Masters in 2007. Timms is hoping to finish the tournament by 5 p.m. Sunday to accommodate not only television, but also the players heading to Augusta.

"We do everything we can operationally to hit that window," Timms said.

Isolated storms were in the forecast for Friday afternoon, creating the potential for another delay. Cabrera and Pettersson were starting their second rounds after 5 p.m. Friday.

Pettersson missed the cut the last two weeks, at Innisbrook and Bay Hill, and blamed poor iron play. He changed his setup on the range Tuesday and hit 16 of 18 greens in regulation Thursday.

"I felt confident with that, but that doesn't always relate to good play," he said. "But I felt like I was striking the ball well again, and I told myself just to play aggressive and shoot at the pins and see what happens."

Cabrera has played at Redstone every year since 2007, the year he won the U.S. Open. He missed the cut there in 2009, then won the Masters the following week.

Charlie Epps, Cabrera's Houston-based swing coach, said the Argentine is concentrating on this week and not thinking about the Masters just yet.

"He wants to play well this week, he's focused on this week," Epps said.

Chris Couch (unspecified injury) and 2010 champion Anthony Kim (shoulder injury) withdrew Friday.