HUMBLE, Texas — Fred Couples is content knowing that his days on the PGA Tour are winding down.

He turned 50 last October and he's having the time of his life this year on the Champions Tour, playing again with old rivals like Corey Pavin and Nick Price. But Couples has also won three straight starts on the senior circuit, and can't help thinking that he's still got enough game to compete with the youngsters.

Couples is back on the regular tour this week, joining stars like Phil Mickelson, resurgent Ernie Els and defending champion Paul Casey at the Houston Open, an event that's embraced its niche as the run-up to next week's Masters.

Couples feels rejuvenated by his success on the Champions Tour and he's putting as well as he has in a long time.

Couples, who will play a practice round for the Masters with Tiger Woods on Monday, laughs off the notion that he's one of the favorites at Augusta National. But he's definitely one to watch at Redstone, where he has a pair of top-4 finishes the last two years.

"I'm fading out on the regular tour a little bit," Couples said, "but this is a great opportunity for me, because I won the last three times on the Champions Tour. Winning is a lot of fun, and so far, this year has been a lot of fun."

Els is riding a streak of his own, with victories in his last two starts. He can become the first player to win three in a row since Woods won five straight in 2008.

The Big Easy isn't totally comfortable with his game, though, after nearly letting last week's win at Bay Hill slip away. He led by five shots with six holes left on Sunday, then hit two shots into the water. Rain forced a suspension, and Els had to return on Monday to make four tense pars and win.

He said his alignment is "out of whack" and he's working with swing coach Butch Harmon this week to iron out the kinks.

"I've been working on that a little bit the last couple of days and I'd just like to have it under pressure," Els said. "Obviously, next week, you've got to do everything right under the biggest pressure you're ever going to find."

Mickelson is another one of 30 players in Houston who's already qualified for the Masters. Mickelson is seeking his first win of the year, but like Els, he's more focused on fine-tuning his game for the season's first major.

"My game this year hasn't been what I expected," said Mickelson, who tied for 30th at Bay Hill last week. "I keep saying it doesn't feel far off. I haven't put together the scores, and I think this week in Houston is an important week for me because I feel like my game has been pretty close."

The players are once again raving about the condition of The Tournament Course at Redstone. Organizers have lured another top-notch field by spreading the word that the course is set up to simulate the conditions at Augusta National, from the fast greens and runoff areas to the light rough and the fairways mowed toward the tee.

"I think it's an advantage for the players who play here going into next week," Mickelson said. "The ball will react certain ways out of the first cut of rough and fairway, getting adjusted to the speed of the greens — all that goes into preparation for next week."

The Houston Open moved to the week before the Masters in 2007, and the results don't fully support the notion that the event is a perfect tuneup.

Mickelson missed the cut in Houston last year, then finished fifth at the Masters. Couples finished fourth in 2008 and third in 2009, but missed the cut at Augusta both years. Casey beat J.B. Holmes on the first playoff hole here last year to secure his first PGA Tour victory, then said he was disappointed with a tie for 20th at The Masters.

"I think physically and emotionally, it took a little bit out of me," Casey said. "If you don't have everything in place going into a major, then you're going to be found out. I think that showed where I finished at Augusta the following week."

Inclement weather has become an annual intrusion at the tournament, and thunderstorms are possible on Friday and Saturday this year.

The event has been delayed by bad weather every year since 2006, when it moved to the Tournament Course from the adjacent members' course at Redstone. Last year, rain pushed back the start of the tournament by 2 1/2 hours, and high winds forced the suspension of play later on Thursday.