Still seeking his first green jacket, Ernie Els arrived this week with a new weapon: instructor Butch Harmon.

Ernie Els, shown chipping onto the second green in Tuesday's practice round at Augusta National Golf Club, hopes to tighten up his swing as he works with golf instructor Butch Harmon. (Jackie Ricciardi/Staff)

After working almost two decades with swing coach David Leadbetter, Els changed to the other premier golf teacher. Golf Digest ranks Harmon as the No. 1 instructor.

"David Leadbetter is a very good friend of mine; he's been a mentor of mine for a very long time," Els said. "I just wanted to get a different feel, get different words coming towards me, and just find a bit more about how Butch is teaching.

"He's obviously had a lot of success with a lot of players, and I love the way he changes people's games."

The 38-year-old Els is making his 15th Masters Tournament appearance.

He owns six top-10 finishes, including a pair of runner-up showings.

He finished second by three shots to Vijay Singh in 2000. Four years later, Els fell victim to Phil Mickelson's birdie putt on the final hole.

"It was his first major (victory), and to win it in that fashion and that style was wonderful," Els said of Mickelson. "But I still ... wake up in a cold sweat every now and again because of that putt."

Els, the world's third-ranked player, is looking for his fourth major victory, his last coming at the 2002 British Open.

He first received help from Harmon last month, three weeks after winning the Honda Classic, his first PGA Tour victory in four years.

Despite the victory, Els said his posture was a problem; he turned his hips and shoulders too much on his backswing.

"I'm quite a flexible guy, but swinging that long, I get out of sync with my lower body and upper," he said, "so I needed to stabilize that and shorten my backswing a little bit and really get the club out in front of me."

Typically somewhere near the Masters lead on the weekend, Els -- who has entered Sunday in the top 10 nine times -- posted his worst finish in Augusta just last year.

He opened with rounds of 78-76 for his first missed cut here since 1995.

With Harmon's help, Els said, he hopes he can trust his swing Thursday.

"It's not like I'm changing my swing to a Furyk or, you know, Tiger's swing or anything like that," he said. "It's still going to look like my swing; it's in a little different position.

"If I can slide a couple of good ones to go, I can take the momentum and move forward from there."

Reach Chris Gay at (706) 823-3645 or chris.gay@augustachronicle.com.