OXFORD United must show the same qualities which were on show at Portsmouth if they are to spring a cup upset tonight, according to Andy Melville.

The U’s made a flying start to the season with a 4-1 win at Fratton Park on Saturday and will attempt to build on the success as they head to Charlton Athletic in the Capital One Cup.

Chris Wilder’s men will start as underdogs against their Championship hosts, but first-team coach Melville believes they have a chance of reaching round two if they can reproduce Saturday’s performance.

“We’re looking forward to it. It’s three days on from a winning start and momentum is massive in football,” he said.

“We were pretty solid on Saturday and first and foremost we have to do the same – be organised and compete.

“Those are the first things in our minds, then you can let your flair players perform with a bit of freedom.

“It’s a really good environment to go to, just as it was at Portsmouth on Saturday.

“The players should thrive on it. They shouldn’t go with any nerves and it’s one of those places where everything takes care of itself.”

Although United want more of the same, their team is likely to change.

Wilder hinted on Saturday they look at a couple of younger players, with Callum O’Dowda, Ryan Williams and Josh Ruffels all in contention to make their first-team debuts.

Addicks boss Chris Powell is also considering rotating his squad, but the hosts go into the game under some pressure after losing 2-1 at newly-promoted Bourne-mouth on Saturday.

Melville said: “Charlton will look at our result, but first and foremost will look at their own.

“They will have watched the game back and won’t be happy with certain things and will want to put that right.”

Charlton will have to make one enforced change, with Bradley Pritchard starting a three-game suspension for a red card on Saturday.