KARL Robinson admitted Oxford United ran out of steam in their 1-0 defeat at Plymouth Argyle.

The U’s left Devon pointless thanks to Morgan Whittaker’s 70th-minute goal, with Kyle Joseph sending a golden chance over the crossbar moments later.

The visitors did not create another opportunity as their unbeaten run in Sky Bet League One ended at three matches.

Read the match report here

United are still without five players through injury and Robinson felt the lack of depth showed in the closing stages.

The U’s head coach said: “After 70 minutes I thought it was really even, other than their set-plays.

“I thought in the first half we were probably the team that had the impetus after the first five or ten minutes.

“When we made the subs I thought we went off it and didn’t finish with that sting we normally do.

“Our confidence got shot, because the players in there give everything every week.

“We thank the fans for travelling down, we’ve let them down because we always want to win and know how hard it is to come this far south on a Tuesday night when people have got work, and the cost implications of that.

“The players are doing everything they possibly can, but it's difficult for us in these big games right now.”

Third-place Argyle started on top and created several opportunities from corner routines off the training ground, with the U's failing to stop the chances.

United weathered the storm and reached the break level but Robinson admitted they had to be better.

“One of our players should have stepped onto someone and it was spoken about at half-time," he said.

"We did ride our luck from the set-plays."

Whittaker and Niall Ennis were the hosts’ first changes just after the hour mark and the pair combined for the winning goal.

Sam Long found Joseph at the back post five minutes later, but the on-loan striker could not keep his effort down as he slid in at close range.

Robinson said: “The lad works his socks off, I don’t know how he’s missed.

“They’ve rode their luck more than we did, I don’t remember them missing a really good chance.

“Even their goal is 18 yards out and Easty probably could do better, he’s come in (to the dressing room) and the first thing he said was ‘I should save that’.

“That’s the difference right now.

“The substitutions we have behind us are more suited to holding on to a game.”

Robinson also revealed why James Henry went down injured in the warm-up, with the 33-year-old receiving treatment before recovering to start the game.

He said: "Slavi (Spasov) went into a tackle and caught his Achilles.

"There was a little bit (of concern), but he was fine."