AFTER teeing up an Arsenal double in the space of seven days, midfielder Jack Colback believes Sunderland now have the belief to give Arsene Wenger’s team big worries on Wearside.

In overcoming Middlesbrough in extra-time in the FA Cup replay at the Riverside Stadium on Wednesday, the Black Cats have set up a fifth round tie with the Gunners at the Stadium of Light.

That will arrive just a week after Arsenal’s first visit to Wearside this season, when Sunderland are tomorrow looking to further highlight how much progress has been made during Martin O’Neill’s short spell in charge.

Of O’Neill’s 13 games, Sunderland have lost just two, so inconsistent Arsenal – who have a crucial Champions League tie with AC Milan sandwiched in between – will be wary of the threat.

“It’s a fantastic opportunity for us. They will come up to our place twice and I’m sure they will believe they can win but we will too,” said Colback.

“We know what to expect from them. They like to pass it well but so do we too. It’ll be an open and enjoyable game – hopefully it will be a win. We take the game on Saturday first and then go from there, we won’t start to think about the FA Cup tie until after this weekend.”

After such a depressing start to the season, which also included an earlier Carling Cup exit, Sunderland fans cannot believe how quickly things have turned around under O’Neill.

The Northern Irishman, who is still many people’s preferred choice to replace Fabio Capello as England boss, has not only guided Sunderland in to the fifth round of the FA Cup, he has also lifted them up to eighth in the Premier League.

“He’s brought a great self belief. He’s installed a lot of confidence in the players and he just shows that belief in us,” said Colback.

“It rubs off on the pitch.

Maybe we’ve had that little bit of luck – like in the Blackburn game, for example – two great strikes won us that game but that kick started our season.

We’re just going into games expecting to win.

“Unbeatable probably isn’t the right word for how we feel but we’re going into every game extremely confident. We know if we set out right and do our things well we’ve got a chance.”

Colback, who has also played full-back, is playing in central midfield again after taking his chance following the injuries to Lee Cattermole and David Vaughan.

His sweet volley that opened the scoring at the Riverside on Wednesday was his second of the season and he is confident more goals will be around the corner.

The Killingworth-born 22- year-old, who also found the net against Everton on Boxing Day, said: “The great goals just come from the self belief and the confidence that the gaffer has given us and put into us.

“We’re having a go from all angles now and it seems like nine times out of ten they are going in. That is great for us.

“I think the manager’s just increased our self belief. Results breed confidence and we’re going into every match believing that we can win and we should win.

“So it’s great times to be at the club.”