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Wednesday night’s win over Barcelona was as good as it gets for Arsenal fans, but the challenge now for Arsenal is to keep it going in all the competitions.

Going to a ground like Leyton Orient after all the hype of playing Barcelona will certainly be an interesting challenge for players who have to refocus quickly.

The reason the FA Cup is such a great competition is because of ties like this one, because if Arsenal are not switched on mentally they could get embarrassed like so many teams in the past have done.

People always remember when we lost to Wrexham in 1992, but funnily enough we actually played ok that day, led 1-0 and should have been three or four up in the first half.

But Wrexham showed great spirit to hit us with a couple of goals late on, and they had a famous win. The same could happen to Arsenal on Sunday if they don’t have the right approach.

We have seen in the earlier rounds and against Ipswich in the first leg of the Carling Cup semi-final that it is not always easy against teams who are having their day in the spotlight, and Orient will give Arsenal a game on Sunday, make no mistake.

But Arsene Wenger has made it clear he values the cups this season and should get his team in the right frame of mind. With Stoke to come in midweek and then the Carling Cup final, it’s a huge period for the club. We will find out a lot about this team in the next month or so.

For me, the Premier League title is now a two-horse race. Manchester United and Arsenal are going to battle it out over the last dozen games and it should be a close and fascinating confrontation.

After Monday night’s result Chelsea have left themselves too much to do. I have always felt they had the quality to put a run together and get closer to the top again, but at the moment they will be more worried about finishing inside the top four.

It is hard to believe we are saying that before February is out, but that has been the scale of their decline this season. They started well but the season is long and things can change.

Arsenal will still be hoping to get a few favours from Chelsea in their games against United, and you have to say the fact United still have to play Chelsea twice, and Arsenal and Liverpool away, gives the Gunners a great chance of taking advantage.

But United are still the favourites – they have only lost once and showed again on Saturday that they have the players to win the big matches.

Arsenal’s performance against Wolves also impressed me because there had been a lot of stick flying around after what happened at Newcastle and a game like that can affect your confidence in strange ways. Wolves had also beaten United in their previous game and were on a high but it was a one-sided win. Another one of those against Stoke on Wednesday would do nicely