(Photo credit: Jeff Lange / USA TODAY NETWORK via Imagn Images)

South Africa's Ernie Els shot a 5-under-par 67 on Saturday to take a one-stroke lead at The Ally Challenge in Grand Blanc, Mich.

Els avoided any bad holes at Warwick Hills Golf & Country Club, shooting par or better on every hole. He opened with a birdie on the first hole of the day, added one on the ninth, and then on the back nine he had three more on Holes 10, 12 and 15.

The 55-year-old is playing strong golf and looking to build off two straight top-five finishes, at the ISPS HANDA Senior Open (T5) and the Boeing Classic (T3).

Els caught and surpassed first-round leader Stewart Cink, who had shot an impressive 10-under round on Friday. On Saturday, Cink was solid if unspectacular, balancing three bogeys with four birdies.

'Surprised I'm leading,' Els said. 'Yesterday it was just crazy scoring. You kind of expect the same and not quite the same. Happy today, but there's a lot of guys at 10 and 9 and 8.

Back-to-back bogeys on Holes 14-15 for Cink could ultimately prove costly for what is shaping up to be a competitive final round. Four more golfers are a stroke back.

'it's not really a swing adjustment, it's more of just like a focus and an intent adjustment that I'm going to make for tomorrow,' Cink said. 'I know I have what it takes to compete really well deep in these tournaments and I plan to do just that tomorrow.'

The aforementioned foursome -- Denmark's Soren Kjeldsen (65), South Africa's Retief Goosen (66), and Australia's Mark Hensby (68) and Cameron Percy (67) -- sit at 10 under after two rounds.

Kjeldsen finished his day with three straight birdies and said he can't wait to get back out there.

'It's great, great to have another chance to go out there and see if I can play well.'

The top nine is rounded out by three golfers tied for seventh at 8 under: Thailand's Thongchai Jaidee (65), Heath Slocum (66) and Argentina's Ricardo Gonzalez (68).

--Field Level Media