Five pairs were tied for the lead after the second round of the QBE Shootout as Bubba Watson and Charles Howell's 66 saw them move into contention.

Harold Varner and Ryan Palmer equalled the tournament's lowest round on Friday with a 17-under 55 to take a two-shot lead through 18 holes, yet they had company at the top after Saturday's round.

Having made gains at 16 of the 18 holes in the first round, Varner and Palmer had three bogeys on Saturday at the event in Naples, Florida.

Watson and Howell had a blemish-free round and back-to-back birdies at 17 and 18 saw them reach 19 under par through 36 holes, the same score as Varner and Palmer and three other pairs.

Brendon Todd and Billy Horschel, Jason Kokrak and JT Poston and Kevin Tway and Rory Sabbatini were the other duos that had a share of the lead.

Ian Poulter and Graeme McDowell managed to record the joint-lowest round of the day, though, following up their 61 with a 65 on Saturday.

Four birdies in five holes between the fourth and eighth helped them reach 18 under par for the tournament, one shot back ahead of Sunday's third and final round.

Harold Varner and Ryan Palmer equalled the lowest round at the QBE Shootout with a 17-under 55 on Friday.

The American duo birdied 15 of the 18 holes and eagled the 17th, with their only pars coming at the fifth and 16th.

Varner drained a 20-footer on the last to tie a record held by four other teams at the stroke play event.

That first-round score gave them a two-shot lead over Jason Kokrak and J.T. Poston, with the duo of Ian Poulter and Graeme McDowell in a tie for eighth after their 11-under 61.

"We're just having fun," Varner told the PGA Tour's website.

"We enjoy each other's company, even if it's not on the course, and it just meshed really well today.

"It's not like some person did this or that, it was just a lot of fun. I enjoy that team aspect, we were pretty pumped for this."

Had they shot 18 under par they would have broken the competition's single-round record, and Palmer joked those two pars cost them.

"I was really wanting 18, I thought we could get there," he added.

"You had the mental lapse, you make two pars like that..."