Jason Dufner does some damage in a short stretch, trails by 1 shot at Memorial

David Lingmerth, of Sweden, watches his approach shot on the ninth hole during the second round of the Memorial golf tournament, Friday, June 5, 2015, in Dublin, Ohio. (AP Photo/Jay LaPrete) (The Associated Press)

David Lingmerth, of Sweden, reacts after a birdie on the 18th hole during the second round of the Memorial golf tournament, Friday, June 5, 2015, in Dublin, Ohio. (AP Photo/Darron Cummings) (The Associated Press)

DUBLIN, Ohio – Jason Dufner made a 3 on a par 5 and a 5 on a par 3. That was before he made a hole-in-one.

A wild back nine sparked Dufner to a 5-under 67 on Friday and left him one shot behind David Lingmerth of Sweden midway through the second round of the Memorial. Lingmerth had a bogey-free 65 and already has 14 birdies over two rounds at soft Muirfield Village.

Lingmerth was at 12-under 132.

Dufner didn't have much to say, speaking only to Ohio-based reporters. But he has never had a stretch like this. He took double bogey on the par-3 12th hole. He made birdie on the 14th. He made eagle on the par-5 15th. And he hit 6-iron into the hole on the par-3 16th.