Golf:Luke Donald's quest to regain the world number one spot was boosted by an impressive seven-under-par second round at the Classic of New Orleans today. The 34-year-old needs to finish in the top seven to move back to the top ranking, and that looked unlikely after a one-over-par 73 on Thursday left him eight adrift of the leaders.

However, he stormed back into contention, kicking off with a birdie at his opening hole — the 10th — before adding four further birdies and an eagle two at the par-four first to claim a share of 12th place. Jason Dufner holds the clubhouse lead on 12 under, one ahead of Scotland’s Russell Knox.

Australian Greg Chalmers and South African Ernie Els were in a tie for third at 10 under after a 64 and a 66 respectively. Joint first-round leader Ken Duke was one under par through seven holes, while fellow opening-round leader Cameron Tringale made a bad start as he bogeyed the 10th, his first hole.

Graeme McDowell was on three under after six holes of his second round while US Masters champion Bubba Watson was down in a tie for 66th, even par for the day through five holes and one under overall.