Beem finished his round strongly to move into contention

Mike Weir, Aaron Baddeley and Rich Beem moved into a share of the lead at the halfway mark of the Deutsche Bank Championship in Massachusetts.

Weir went two strokes clear before bogeying his last two holes for a 68 while Beem birdied his last four holes to move into contention.

Both Phil Mickelson and Tiger Woods moved up the leaderboard with seven-under pars 64s.

Mickelson is one off the lead with Woods two shots further back.

Mickelson twice chipped in, for birdie on 15 and then for eagle at the par-five 18th, while defending champion Woods covered his last eight holes in six under.

Overnight leader Camilo Villegas of Colombia shot a 72 to be among a group of five players on seven under.

"It was a lot of fun," said Mickelson. "This is what we were kind of hoping for in the first round but you can't get it going all the time.

"It was actually a little more challenging today with the cooler air and the breeze but the greens were so perfect you felt you could make lots of putts.

"We just didn't get it going yesterday but I just sensed that everybody was going to come out ready.

We all needed a good round to get back into the tournament, and that's what we ended up doing."

Woods added: "It was nice to get the putter rolling and I caught fire on the back nine. The whole idea was for me to get something around three or four under par today. Now I'm back in the tournament."