THE time has come for Fernando Torres to prove his worth to Chelsea.

He can do so this lunchtime when he will almost certainly take over from Didier Drogba in the team that faces Arsenal at the Emirates Stadium in what is a crucial London derby in the chase for Champions League qualification.

Drogba, putting aside the time he spent claiming injuries, was superb against Barcelona in midweek, holding the ball up as the lone striker, winning free-kicks, unsettling the Spanish defenders and scoring the goal in Chelsea's 1-0 victory.

It was an all-round striking performance and his manager, Roberto Di Matteo, will expect the same from the Ivorian in the return leg at Camp Nou on Tuesday.

It is why it makes sense to bring in a fresh Torres today in a match which could have a huge bearing on Chelsea's future. Put it this way: there is still a better chance of Chelsea qualifying for next season's Champions League by finishing in the top four of the Barclays Premier League than by winning in Munich next month. Chelsea are currently sixth in the league table but victory this afternoon would leave them only four points adrift of third-placed Arsenal with a game in hand.

Tottenham and Newcastle remain in the mix, but the value of a Chelsea win at the Emirates is obvious. For Torres it could offer redemption after a season in which he has scored just seven goals in 42 appearances in all competitions.

Those figures show up particularly badly when you compare them with Arsenal's Robin van Persie who has 34 times in 43, 27 of them in the league. Quite where Arsenal would be without Van Persie's input is difficult to gauge. Suffice to say it is doubtful they would be confident of their own Champions League place next season.

The problems at Arsenal remain the same as they have been, well, since they last won a trophy, the FA Cup, in 2005: a defence which has its shaky moments as it did in the defeat to Wigan on Monday night; too many lightweight players such as Theo Walcott and Tomas Rosicky, who sparkle one moment and then fail to ignite the next. A lack of a plan B, too, means that when the Arsenal pretty patterns fail to open up the opposition there is precious little else to fall back on.

The loss of Mikel Arteta with ligament damage for the rest of the season is a blow considering he has proved to be a creative playmaker, but the real solution for Arsene Wenger would be to buy top-notch quality and experience in the summer. In the manger's world of thrift and the pursuit of youth, that is unlikely to happen. By rights, Arsenal should have the edge today, if only because they should be fresher and do not have the distraction of a Champions League semi-final just days away.

But there is something about Chelsea under Di Matteo that is beginning to resemble a force of nature.

They have regained the trust and the confidence that were glaring by their absence under Andre Villas-Boas. They are playing with organisation and commitment and without fear.

They may be an ageing force but they still retain quality. Most of all, they have regained that uncanny ability to win the big matches when the pressure is at its greatest.

They will need that in Spain on Tuesday, but the momentum is with Chelsea. If Torres can feed off that then the chances are they might go to Spain on the back of victory in London.