AKRON, Ohio — Ryo Ishikawa amazed even his peers in a charity-driven sport when he pledged in March to donate his 2011 earnings on the course to tsunami-relief efforts in his native Japan.

Ishikawa could increase the donation Sunday in a World Golf Championships event.

Coming off a missed cut in Japan, never better than 20th in stroke play in America, the 19-year-old made six birdies and twice escaped trouble in the trees Saturday for a 6-under-par 64 that put him in the final group and one shot behind 31-year-old Australian Adam Scott in the Bridgestone Invitational.

Along with earning a $1.4 million payoff, Ishikawa could become the youngest winner of a PGA Tour event in 100 years.

"I think it's a little too early to think about winning this whole thing as of now," Ishikawa said.

Scott poured in four birdies on the back nine for a 4-under 66 and was at 12-under 198, the lowest 54-hole score at Firestone in 10 years. He will play in the last group with Ishikawa.

"Today was a good round because I wasn't really feeling it, although I was swinging well," Scott said. "Just a couple shots got away from me throughout the round, and I somehow managed to straighten it out early on the back nine and played really nicely coming in, so I was very happy with this round."

Jason Day (66) of Australia was tied for second place.

Ryan Moore (74) of Puyallup dropped into a tie for 18th at 4 under after being tied for the lead entering the round.

American Tiger Woods (72), a seven-time winner at Firestone, was tied for 38th place at 1 over in the field of 76. This is the former world No. 1 player's first tournament in nearly three months.

"I've just got to put together a good round and let it build," said the 28th-ranked Woods, who is recovering from a knee injury.

One of Woods' shots struck fan Brady Klotz in the back and bounced close to the fairway.

"I apologize. I didn't mean to hit it over there," Woods told Klotz as he handed him a signed glove.

Last month, Woods announced he was parting with caddie Steve Williams. Scott hired Williams.

Other tournaments

• Scott Piercy reeled off eight consecutive birdies to post a 28 on the front nine and eagled the 616-yard closing hole to set the course record with an 11-under 61, taking a two-stroke lead after three rounds of the Reno-Tahoe Open.

Piercy enters the final round of the PGA Tour event in Nevada at 13-under 203. Josh Teater (66) was in second place.

Piercy, 32, is winless in three years on the Tour. "I told my caddie yesterday if I can keep hitting it well and get a few balls to go in the hole, we might do something special," he said.

Kirk Triplett (68), a graduate of Pullman High School, was tied for 21st place at 6 under and ex-Washington Huskies player Alex Prugh (74) of Spokane was tied for 57th at 2 under.

• Peter Senior (5-under 67) and John Huston (68) were tied for the lead at 12-under 132 after two rounds of the 3M Championship, an event on the 50-and-older Champions Tour in Blaine, Minn.

Seattle native Fred Couples (69) and Bernhard Langer (70) were among the players tied for 17th place at 6 under.

• Ex-Washington Huskies player Troy Kelly shot a 9-under 62 in the third round of the Cox Classic, a Nationwide Tour event in Omaha, Neb.

Kelly was tied for sixth place at 15-under 198, five strokes behind leader J.J. Killeen (63).

Jeff Gove (65) of Seattle was tied for 20th at 12 under.