Manager Chris Wilder admitted defending set-pieces is Oxford United’s Achilles heel after they again conceded from a corner in Saturday’s 2-1 defeat at Northampton.

The U’s slipped to tenth in npower League Two as their magnificent run of six wins from seven, and three away wins on the bounce, came to an end.

The Cobblers struck first just before the break when their captain, Andy Holt, was unmarked to glance in a header at a corner.

Although Tom Craddock equalised, with his 12th of the season, Leon McKenzie headed home the winner on 67 minutes.

United let in goals from corners against Bradford at the Kassam Stadium last week, and against Southend in their previous home game on New Year’s Day.

And it’s now 20 games since a clean sheet.

But Wilder felt there was not much else wrong with the performance at Sixfields, apart from picking out the right final pass.

“I think we’re going in the right direction,” he said.

“We controlled the first half and were disappointed to go a goal down to a set-piece, that’s our Achilles heel at the moment, yet we came back into it.

“But the game got a bit stretched, we left ourselves a bit open for the counter-attack – and then Holt and McKenzie showed their qualities.”

Wilder was more frustrated that good scoring opportunities, created by strong runs from Damian Batt and Sam Deering, were not finished off, something the U’s will hope to put right against Shrewsbury at the Kassam Stadium tomorrow night.

“We got into four or five great positions, and it was our final ball that let us down,” he said.