Fred Couples and Corey Pavin make it old-timers’ day at Riviera

Fred Couples is 51 years old, with a back so painful that he said sitting and sleeping sometimes seem impossible. Corey Pavin is 51 years old and coming off his job as captain of the 2010 Ryder Cup team, a job that is for guys mostly done playing on the PGA Tour.

Couples won the tournament at Riviera Country Club in 1990 and 1992. Pavin, a former UCLA star way back when, won it in 1994 and 1995.

And for a moment or two Thursday afternoon during the first round of the 2011 Northern Trust Open, there was Pavin alone in the lead at five under par and Couples two shots behind.

When the day ended, there were nine players tied for the lead at four-under 67 and none of them was Pavin or Couples. Couples was only a shot behind, though, with his 68. Pavin was two behind after he bogeyed three of his final six holes, including his last two, to finish at 69.

Pavin, one of only two players to reach five under Thursday, was one of the final men to finish before the first round was called because of darkness. Pavin finished his first round on the front nine and especially lamented a chip on the eighth hole that, he said, “came out a little faster than I thought and then I hit the worst putt I hit all day.

“And on nine I hit a good drive and a really good five-wood in there and it just didn’t get up over the hill. I was surprised where the ball was.”

Couples, who also started on the back nine, had a stretch where he recorded three straight birdies (on the 17th, 18th and No. 1 holes), but after his round spoke about his back pain.

“I’m going to maybe do some things [about his back] after this tournament,” Couples said.

“I’m going to get an MRI…I can’t stand. I can swing a club, but I just can’t sleep. It’s like the biggest toothache ever all day long and I’ve had enough. So I’m going to go see if I can do a couple of things to take the pain away.”

Winning this tournament might also take some of the pain away for Couples, but that seems unlikely.

“Tomorrow is going to be a rough round,” Couples said.

diane.pucin@latimes.com

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