One of three co-leaders after the first day of action at the Memorial Tournament, PGA rookie Rickie Fowler separated himself from the pack on day two with a round of 66 leaving him 13-under for the tournament.

“I just feel really comfortable getting out and seeing my name on top of the leaderboard,” said Fowler. “It’s not making me feel much nerves at all.”

Shooting 65-66 for a combined score of 131 through two rounds, Fowler is now tied for the lowest two-round total in Memorial history.

Chasing Fowler is yesterday’s co-leader Justin Rose, alone in second at 10-under par and Tim Petrovic and 2002 Memorial champion Jim Furyk tied for third at 9-under.

At the rate Fowler is playing, however, it seems as though the 21-year-old cooling off is the only way the field can catch him.

“If he goes out and plays well, it will be tough to catch him,” said Furyk. “If he goes and shoots another 6- or 7-under, he’s going to have a huge lead. If he doesn’t, he’ll let some other guys back in the tournament.”

Following an opening round 67, Mickelson cooled off in round two, shooting 1-under par, good for a tie for eighth going into the weekend.

Defending champ Tiger Woods came out stronger in day two but failed to capitalize on a few good opportunities, leaving him 10 shots off the lead at 3-under par.

“I hit more good shots today than I did yesterday and really putted well today,” said Woods of Friday’s performance. “I had five lip-outs today, so it could have been a pretty good number.”

The cut for the tournament came at 1-over par, leaving 71 players left to battle it out over the weekend for the 2010 Memorial crown.