By Mark Lamport-Stokes

PACIFIC PALISADES, California (Reuters) -

American Matt Kuchar endured a painful bee sting while climbing into contention at the Northern Trust Open in Friday's second round.

The three-times PGA Tour champion was stung as he lined up a birdie putt at the par-three sixth, which he then missed, before going on to card a two-under-par 69 at Riviera Country Club.

"I haven't been stung by a bee in probably 20 years," world number 13 Kuchar told reporters after posting a four-under total of 138, two strokes off the lead. "I had stopped being scared of bees as a matter of fact. The thing got me, and it was really painful. It was not much fun."

Kuchar was stung on his forearm, and then missed a six-footer for birdie before tapping in for par.

"I wasn't quite sure what was going to be the end result of a bee sting," said the 33-year-old, who won last year's World Cup for the United States in partnership with Gary Woodland.

"It felt like my elbow was a bit on fire after the bee sting, but I kept going. They (doctors) said if you have trouble breathing, stop and we'll try to help you from there.

"But thankfully everything continued to go pretty normally. I continued played some good golf. I had a lot of chances, and played seven and eight and nine pretty well."

Kuchar, whose most recent PGA Tour victory came at the 2010 Barclays tournament, compiled three birdies and a lone bogey in breezy sunshine at Riviera where the small greens have been difficult to negotiate this week.

"Getting balls close to the pins is a tricky thing because of how firm they seem to be," said Kuchar, who set a PGA Tour record last year by piling up $4,23 million in earnings without winning a tournament.

"That first bounce is always a big bounce, and then short of the greens is so sticky you really can't land the ball short."

(Reporting by Mark Lamport-Stokes; Editing by Frank Pingue)