Ahead of Sunday afternoon's match at Stamford Bridge, Darren Fletcher offered the most concise summary of Chelsea's shift in style. "It used to be a big, strong, physical side," the Manchester United midfielder said. "Now you tend to be facing more Barcelona-style players – the small, intricate ones who get in the pockets behind you and play the killer pass." it's clear to whom he was referring – Eden Hazard, Oscar and Juan Mata.

Having spent 10 months out with ulcerative colitis, Fletcher has had plenty of time to study the development of Sunday's opponents, and the Scot believes he has identified a weakness, too. "It gives you opportunities to break at them," he continued. "If we do win the ball, it will leave a lot more spaces than you normally expect."

After starting the campaign with Ramires or Ryan Bertrand in addition to two playmakers, Roberto Di Matteo first fielded the rotating triumvirate five weeks ago. On their collective debut, they crowded the centre of the pitch, making it easy for the narrow Stoke defence. "It certainly needs more work and practice to tactically integrate them perfectly into our system," Di Matteo said after a late 1-0 win. "But it's just a question of time."

Di Matteo is committed to the strategy, bravely fielding all three at Arsenal and Tottenham, as well as at home to Norwich. They reappeared against Shakhtar Donetsk in midweek after Frank Lampard's injury, but Chelsea were outclassed, and the contrast was huge – the Ukrainian champions offered cohesive movement and assured interplay, while Chelsea relied upon spontaneity.

But the signs remain promising. The trio are similarly creative but distinct enough to provide a varied attacking threat: Hazard is primarily a dribbler; Mata a passer; and Oscar offers an unusual blend of clever positioning and a burst of pace. The Brazilian acts as a decoy – the most permanently central player, yet the humblest creative threat – he occupies opposition midfielders, allowing Hazard and Mata to drift inside unchecked. The performance at White Hart Lane last Saturday showed the potential of this combination, particularly on the break. For Mata's first goal, his one-two with Hazard ripped through the centre of the Tottenham side, beautifully outlining the point of this system – those two are currently the Premier League's most prolific creators, with five assists each.

Yet Fletcher is right about Chelsea's weakness. Their transitions from defence to attack are rapid, but their retreat into a defensive shape is often sluggish; in allowing his playmakers positional freedom, Di Matteo risks his side being caught on the break. Barcelona, say, ensure players are covering the width of the pitch, not merely to offer different angles of attack, but to retain a good shape to press immediately when the ball is lost. If Chelsea's three attackers and Fernando Torres are all central, the flanks are ripe for opposition counterattacks.

Chelsea will have worked upon defensive shape, but attacking remains the priority. Having handed Roman Abramovich his first European Cup, Di Matteo is now building the free-flowing, creative, exciting side the Russian craves.