Birdieing five of his final eight holes, Phil Mickelson finished with a round of 4-under 66 to trail leader Bubba Watson by two shots in Thursday's first round of the Bridgestone Invitational.
Teeing off at No. 10, Mickelson shot 1-over on the back nine with bogeys at Nos. 14 and 15 with a birdie at 16. He found his game on the front nine, birdieing Nos. 2, 3, 6, 7 and 9 for a 30 on the par-70 layout.
His best shot came at the 469-yard par-4 No. 6, when he pulled his iron shot to the right and was merely hoping to get up and down to maintain momentum. His lob wedge went in for birdie.
''When that lob shot went in the hole it gave me a nice boost,'' Mickelson said. ''I made birdie and was able to get two more coming in.''
Playing partner Rory McIlroy said that was the best shot he's seen this year. Asked where it ranked for him, Mickelson said, ''It was a good one. There were some at Augusta that I remember a little more fondly than Thursday at Akron. It wasn't as hard as it looked to get up and down, but I was certainly fortunate for it to go in.''
Mickelson's best finishes at Firestone Country Club were seconds in the 1998 and 1999 NEC World Series of Golf. He's struggled here since 2003, with his best performance a tie for fourth in 2008.
''It was as a good day in that I got off to a poor start and was able to turn it around,'' Mickelson said.
He credited swing coach Butch Harmon with a good idea for his driver.
''Butch had a good idea to go to a shorter driver,'' Mickelson said. ''So I went to the guys at Callaway and had that FT9 head in a shaft that's only 44 inches and a shaft that's also 20 grams heavier. It alters the characteristics of the head. I've got to give the guys credit, to be able to get the spin rate and the ball flight right. I seemed to hit the ball a little bit straighter with it. My misses were inside the tree line, so I always had a shot into the green and I thought that led to more aggressive iron shots.
"It's only been a couple days. This might actually be in the bag for a while.''
Mickelson praised 21-year-old McIlroy of Northern Ireland, who finished at 2-under.
''He's fun, he's interesting, he's a smart guy, he's really got a great demeanor,'' Mickelson said of McIlroy. ''He's always upbeat, great to be around, not to mention his talent.''
Mickelson said he was amazed by the prowess of young players like McIlroy, Japan's Ryo Ishikawa (18 years old) and American Rickie Fowler (21).
''I look at the guys today in their teens and 20s -- McIlroy, Ishikawa, Fowler -- their ball striking is so superior to where myself or other players my age were in our teens and 20s,'' Mickelson said.