Stewart Cink got his Saturday off to a rousing start with an eagle on the par-5 first, then put together a flawless rest of his round to shoot a 6-under-par 66 and grab the lead by three strokes at the Ally Challenge in Grand Blanc, Mich.

The 51-year-old has four top-10 finishes this season but no career wins on the PGA Tour Champions. This is his first start at the Ally Challenge, though he did finish fifth at Warwick Hills for the Buick Open on the PGA Tour 20 years prior in 2004.

"Golf is just a funny game, and it can just leave you in a hurry," Cink said. "I'm aware of that. It's going to take a lot of discipline, a lot of patience and really just being true to who I am and how I play tomorrow to get this thing done. But I'm looking forward to the challenge."

Cink followed up his three-shot opener (featuring an 80-foot putt) with par-level golf over the rest of his front half, then closed with four birdies over his final nine holes, including birdies on Nos. 11, 13, 14 and 16.

He was a perfect 18-for-18 hitting greens in his second round while getting to 11-under 133 for the tournament.

"Sometimes moments like (the eagle) can kind of send shock waves through your system," Cink said. "While it didn't really shock me, I just played really good golf after that and just didn't show any results.

"I hit a lot of fairways and had a lot of birdie putts and just grazed the edges for like nine straight holes, and meanwhile the scoring was moving past me. It could have been a moment to get a little frustrated and start trying a little too hard, but I knew that the really scorable part of the course was coming. Some of the early holes on the back nine are very gettable if you keep it in play. I was proud of myself for being patient."

South Korea's K.J. Choi followed up a bogey-free, 6-under 66 on Friday with a 2-under 70 on Saturday, falling into a three-way tie for second.

Choi suffered a bogey on the seventh, but he rallied for birdies on holes 10 and 12.

He's tied with David Branshaw (69) and Australia's Steve Allan (66) at 8 under after two rounds.

Branshaw, who was a stroke behind Choi on Friday, remained in second place by balancing three bogeys with six birdies.

Allan had seven birdies against a single bogey (on the par-4 15th) to stay within striking distance. He was asked about his strategy going into Sunday.

"You've just got to play well," Allan said. "If I go out and try too hard for birdies early, it ends up in disaster, so I just try to let the round play out. We don't need to birdie the first few holes to have a good round. You can build into the round and have a hot finish, too. I'm just going to go out there and try and play well."

Bob Estes (69) and Australia's Rod Pampling (70) are a stroke behind that trio, tied for fifth at 7 under.

Kirk Triplett (67) and Brett Quigley (71) are tied for seventh at 6 under.

Charles Schwab Cup money leader Ernie Els of South Africa remains behind the leaders at 2 under (T31).

--Field Level Media