BLAINE, Minnesota (Ticker) -- The final grouping Sunday at the 3M Championship will consist of a club pro and a pro's pro.

Unheralded James Mason was caught by Senior PGA Tour star Hale Irwin but maintained a share of the lead after Saturday's second round of the $1.75 million event.

Mason managed a par 72 and is at 8-under 134 after two trips over the TPC of the Twin Cities. Irwin carded a 2-under 70, erasing a two-stroke deficit and moving into position for his third win of the season.

A club pro from Dillard, Georgia, Mason stunned the field Friday by setting the course record by posting his lowest round on the elder circuit, an 8-under 64. Winds gusting up to 30 miles per hour kept scores much lower the second time around.

"The course played good but longer today because of the wind," Mason said. "The greens are still holding well but they are getting crustier."

"With today's conditions, the field played like they were trying not to lose rather than trying to win," Irwin said. "I was off balance a lot today with the wind. The cross winds were tough."

The leading money winner in Senior Tour history, Irwin also dropped off a bit after opening with a 66. He has 34 career titles to one for Mason, who won the NFL Golf Classic in June as a Monday qualifier.

"I'm happy to be where I am right now," Mason said. "I just want to stay close to him tomorrow. I'm gaining confidence each day."

The men played together Saturday and will do so again Sunday. They are at 8-under 136, three shots in front of a group of five that includes Bob Gilder, who won a pair of tournaments in playoffs last month.

Mason started as if he were going after another course record, birdying three of the first six holes. But he undid his good work with a double-bogey at the par-4 seventh and a bogey at the par-3 eighth.

A 15-foot birdie putt at the par-4 15th was offset by a bogey at 16.

"Other than No. 7 and No. 16, I was ecstatic with how I played," Mason said. "It was tough out there. I'm happy with how I played. I'm very pleased with where I am. I have a chance to win the golf tournament."

"His double-bogey was unfortunate for him but fortunate for us," Irwin said.

Irwin had a less eventful round, erasing his lone bogey at No. 8 with three birdies.

"You could not be too aggressive today," Irwin said. "I don't think anyone in our group felt comfortable. I'm very happy with today. I didn't take myself out of it."

Irwin has held or shared the lead heading into the final round 32 times and has won 23 of those tournaments. However, he is 0-5 in playoffs, including a pair of extra-hole losses in the last month.

Gilder and Bruce Fleisher shot 68s to move to 5-under 139. They are tied with Allen Doyle, Rocky Thompson and Leonard Thompson, all of whom carded 71s. Fleisher has shot 14 straight rounds at par or better.

Sunday's first group will consist of the legendary Arnold Palmer and Baseball Hall of Fame member Johnny Bench.