OXFORD United will not know the severity of Cameron Brannagan's injury until later this week, says Karl Robinson.

The midfielder went down with a dead leg in the closing stages of the U's 2-1 defeat at AFC Wimbledon and was replaced by Alex Gorrin.

Robinson expects the extent of the problem to become clear in the next couple of days, with United at home to Plymouth Argyle on Saturday. 

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The U's head coach said: “We don’t know.

"It sounds a lot worse than it is, but we'll see how it settles down over the next 48 hours."

United struck first in a high-intensity contest at Plough Lane, Josh Ruffels placing an effort into the far corner seven minutes after the break.

But the game turned when James Henry saved Will Nightingale's goalbound effort with his hand, which saw the U's midfielder sent off and allowed Joe Pigott to equalise from the penalty spot.

Alex Woodyard made it 2-1 moments later and the ten men of United could not find a second goal, despite enjoying plenty of possession.

Robinson's side fell to seventh in Sky Bet League One, with sixth-placed Charlton a point ahead and boasting two games in hand.

“I’m frustrated, but I love doing this job and those players give me so much," the U's boss said.

“I’m all about performance and I’m all about my team.

"We sometimes know when we haven’t performed and the players will know they've played relatively well."

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Robinson brought on Sam Winnall and Dan Agyei for Matty Taylor and Mide Shodipo three minutes after Woodyard's goal, as United switched to a 4-3-2 formation.

The U's head coach felt the U's coped well with being a man down, although the hosts looked dangerous on the break.

He said: “We like the 4-3-2 split, with the strikers being up against people and letting the centre backs have it.

"Then the higher they go, if the midfield can flatten off as a three they can almost work underneath the two strikers.

"We also like the 3-4-2, with the defenders that we’ve got that can naturally step out and Ruffs and Fordey (Anthony Forde) are very offensive.

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"On the counter-attack it looked like we had one man less, but other than that at no stage did we look like that.”

United's head coach also reserved praise for referee Andy Davies and his team, despite Henry's sending off.

It was the second time the official has dismissed a U's player this season, after he showed a red card - that was later overturned - to Rob Atkinson in the opening-day defeat at Lincoln City.

Robinson said: “The referee, the assistant referees and the fourth official were the best we’ve had this season in the way they conducted themselves.

“I thought they were exceptional.

“It’s important to comment on that, because we comment on the negatives.”