(Reuters) - Kevin Chappell, a three times runner-up this season, has another chance to earn his maiden PGA Tour win after moving into a one-shot lead over Jimmy Walker and Paul Casey after two rounds of the Deutsche Bank Championship in Massachusetts on Saturday.

Chappell, buoyed by an eagle at the par-five seventh after pitching in from the fairway 35 yards out, carded a seven-under-par 64 on the tree-lined TPC Boston in Norton for an 11-under 131 halfway total.

PGA Championship winner Jimmy Walker (64) and Englishman Paul Casey (66) are on 10-under in the second of the Tour’s four FedEx Cup playoff events.

U.S. Open champion Dustin Johnson was within a stroke playing the par-five 18th but ran up a double bogey after slicing his second shot into a hazard and then three-putting. He finished the day three behind.

Chappell has been a regular presence on leaderboards this season with a hat-trick of second places, most notably at the Players Championship in May, and hopes his experience of being in contention will help him over the closing rounds.

“The next 36 holes are going to seem like a long time for me but I feel comfortable in this situation and each time I get near the lead I feel more comfortable,” the 30-year-old told reporters.

“I feel like I’ve handled myself well in the situations I’ve been in this year and can really pull from that ... At some point in the next 36 holes it’s not going to go my way, and it’s going to be about how I handle that.”

Walker is getting back on track after missing the cut the past two weeks. His form dipped following a short break to celebrate his PGA Championship at the end of July.

“Things got a little out of whack,” he said. “I’m just trying to put it all back together. I’ve been chipping and putting really solid. It was just a matter of finding a few more fairways."

Casey said he was starting to regain the sort of form that took him to third in the world rankings in 2010.

“The results haven’t been anything like 2010 but there are some similarities in terms with how I feel with the golf game and the control I feel I’ve got with the golf ball,” he said.

“It doesn’t guarantee anything this Sunday or Monday but it’s trending in the right direction.”

Even if he wins on Monday, Casey will not play in this month's Ryder Cup because the European team has already been finalised.

Chappell, however, could come into consideration for one of U.S captain Davis Love’s four wild card picks.

(Reporting by Andrew Both in Cary, North Carolina; Editing by Peter Rutherford)