OXFORD United’s training sessions have had an added bite this week, according to head coach Karl Robinson.

The U’s are in the middle of a four-game run at the Kassam Stadium against Sky Bet League One promotion contenders.

After beating Portsmouth and drawing with Barnsley, Sunderland are the next test.

And Robinson, whose side are in the relegation zone on goal difference, has been pleased to sense an extra intensity developing in training.

He said: “There’s an edginess around the place at the moment.

“You tend to find it’s not a bad thing.

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“I felt it before Portsmouth and some other games.

“Tackles are going in during training, which I like.

“People might find that quite (strange), but there’s an aggression in training.

“We can’t switch it on and off. I think people have to train to their maximum.

“I’d rather get one or two injuries in training through a tackle, than people go out (in a match) and all of a sudden think they can start tackling, or avoiding a tackle.”

This is only the second time Sunderland have played in the third tier of English football.

They still have players in the squad who appeared for them in the Premier League two seasons ago, but Robinson believes United must not be overawed.

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He said: “They’ve got some unbelievable players, but every team is beatable.

“They’re not invincible, previous results tell you that, so we’ve got to make sure we go into it positively and the players and fans stick together.

“That’s the most important thing, regardless of the ups and downs in the 90 minutes, the criticism or the plaudits can start afterwards.”