OXFORD United’s defeat to Bristol Rovers showed why they cannot let standards slip, according to John Mousinho.

The U’s conceded three times in the final ten minutes of extra time to lose the Emirates FA Cup first round replay 4-3.

Sion Spence twice benefitted from poor defending to make himself Rovers’ hero, when United had already spurned chances to put the game to bed.

It saw the hosts set up a home tie with Sutton United in the second round, while Karl Robinson’s side are out of all three cup competitions.

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They are sixth in Sky Bet League One and well-placed for a promotion push, but Mousinho knows the U’s must improve at second-placed Wigan Athletic on Saturday.

The club captain said: “The whole team has got to have the mentality that we don’t allow crosses to come in the box and we don’t put defenders under too much pressure.

“We need to do better, but it’s one we’re going to have to look at and not take in to our league form.

“If we don’t do the right things we’ll get punished, no matter who the opposition is.

“That’s a timely reminder (before) going to one of the better sides in the league to make sure we knuckle down, prepare properly and don’t get too sloppy.

“It’s a blow, we were looking forward to a home tie if we’d gone through.

“We’re going to have to learn from that and go on from here.”

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The defeat also ended United’s six-match unbeaten run in all competitions.

Mousinho said: “It’s a case of 'get up and go again'.

“If we’d won the game we’d probably talk it up and say it’s one more for the unbeaten run.

“Not taking anything away from how we’ll take this loss, but the league is the most important thing for us at the moment.

“Hopefully that will free up a bit of space and our Christmas period is a little less hectic, so hopefully that will stand us in good stead later in the year.”

The 35-year-old played 90 minutes as he made his first start outside of the Papa John’s Trophy since last December.

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Mousinho was flanked by Luke McNally and Jordan Thorniley in an unusual 3-2-4-1 formation, but enjoyed the test.

He said: “I think the plan was that it might help me more and we’d be playing against a front two, so we’d have an extra body at the back.

“Then Bristol Rovers changed their formation and went to a front three, so it was pretty much one-on-one for most of the game.

“I loved being back, it’s been a long time since I started a game that wasn’t a Papa John’s tie and the pace is different.”