Graeme McDowell watches his approach to the 15th in the second round of the Zurich Classic of New OrelansGraeme McDowell made the cut on the limit after a disappointing 73 as Luke Donald kept alive his chances of regaining the world No 1 ranking from Rory McIlroy in the Zurich Classic of New Orleans.

The Englishman must finish solo seventh at worst to go back to No 1 and he took a step in the right direction when he bounced back from an opening 73 with a faultless seven under par 65 to climb 80 places to tied 22nd at halfway.

That left him six shots behind leader Jason Dufner (65) on six under par but just four strokes outside the top seven at TPC Louisiana.

Dufner leads by a stroke from Scot Russell Knox, Ken Duke and John Rollins after Donald played the back nine in three under and then holed out from 148 yards for an eagle two at the first and then birdied the second and third to get to seven under before parring his way home.

McDowell finished the day tied for 63rd on two under par and will play in the third round with Geoff Ogilvy and newly crowned Masters champion Bubba Watson, who carded a second successive 71 in his first start since winning the green jacket at Augusta National

“Struggled a little on the links today,” he tweeted later. Couldn’t get it going at all. For my sins, I will be out very early tomorrow morning. Time to #golow.”

He was only slightly off the mark and with a two-tee start he goes off the 10th at 11.30am with Ogilvy and Watson, the defending champion.

McDowell dropped an early shot when he three-putted the par three third from 47 feet but got back to level for the day with an eight footer at the fifth after a big drive left him just a wedge to the green.

But he failed to chip and putt for birdie at the par-five seventh, bogeyed the eighth after missing the green from 124 yards and then three-putted the par-three ninth to turn in two over.

He got a shot back when a 98-yard approach to two feet set up a tap in birdie at the par-five 11th and after missing a 15-foot chance at the 13th he drained an 18-footer at the tough, par-four 15th for birdie to get back to level par for his round.

His finish was not quite what he had in mind,  however. Forced to take a penalty drop after a bad drive at the 16th, he bogeyed there and then failed to get up and down from 30 yards at the par-five 18th, missing a nine footer for birdie.