Richard Jolly reports

Reluctant travellers they may be but Besiktas claimed the prize scalp of the world's most expensive team as Chelsea slumped to a first defeat in the Roman Abramovich era.

The Turkish team had never previously won away in the Champions League but a Sergen Yalcin double condemned the 111 million side to defeat at Stamford Bridge.

Excessive tinkering and defensive errors took their toll as, for all the European experience of Claudio Ranieri's expensively assembled side, they were undone on the counter-attack.

Chelsea were architects of their own downfall. They reacted slowly to a quick free kick and Sergen swept in the opener from Uzulmez Ibrahim's cross, a touch off John Terry wrongfooting Carlo Cudicini.

Marcel Desailly has won the Champions League twice. His prospects of a hat-trick receded as he left a through ball for Cudicini and the alert Sergen nipped in for his second, aided by a post and an aimless leap from the keeper. 

Desailly was not alone in having a match to forget as Ilhan Mansiz handed Chelsea a lifeline with an unnecessary red card. Twice, he booted the ball away; twice, pernickety referee Lucilio Cardoso Cortez Batista reached for yellow cards. But having gone two goals down to 11 men, Chelsea could not break down ten.

Ranieri's chosen 11 provokes endless debate and, not content with swapping his players, 'Tinkerman' decided to change formations as Chelsea went 3-5-2. His ongoing quest to give Juan Sebastian Veron a pivotal role appeared grounds for change; for 20 minutes, the Argentine was influential as Chelsea cruised.

Strike partners Hernan Crespo and Adrian Mutu each fashioned themselves a chance and came close from long range. Veron and Frank Lampard had better opportunities, but indecision and a poor touch respectively meant Oscar Cordoba was not troubled.

Then Sergen struck twice in five minutes and Chelsea were floundering. For a quarter of an hour, their response was muted until Lampard, their sole source of drive from midfield, volleyed wide. Veron, with a low drive, and Mutu, with a shot the outstanding Okan Koc did well to block, also threatened.

Time for a 60 million double substitution. Off went Crespo and Mutu, Damien Duff and Jimmy Floyd Hasselbaink coming on. But how Ranieri must have wished that Crespo, rather than the new second striker, Veron, was on the end of Lampard's inviting cross. The wrong Argentinian headed wide.

Ranieri must have regretted his double change - which followed the enforced withdrawal of Celestine Babayaro - when William Gallas was injured in the first minute of the second half.

Gallas limped off, limped back on again and headed wide, a feat Desailly equalled. Then Geremi drew the sole save from the injured Cordoba and both he and Hasselbaink put free kicks past the Colombian's post.

But with Ronaldo Guiaro defiant in defence and Hasselbaink the sole specialist striker on for Chelsea, they suffered just a second home defeat in Europe. Their cheaper predecessors fared rather better - at Stamford Bridge, anyway.

Teams

Chelsea Cudicini, Babayaro (Bridge 23), Makelele, Desailly, Mutu (Duff 45), Lampard, Gallas, Geremi, Veron, Crespo (Hasselbaink 45), Terry.
Subs Not Used: Ambrosio, Johnson, Cole, Gudjohnsen.
Booked: Mutu.

Besiktas Cordoba, Asik, Havutcu, Guiaro, Pancu, Yalcin (Hassan 81), Uzulmez, Giunti (Sulun 68), Mansiz, Zago, Koc (Dobra 60).
Subs Not Used: Kursunlu, Yildirim, Dursun, Metin.
Sent Off: Mansiz (50).
Booked: Mansiz, Havutcu, Giunti, Yalcin, Zago.

Goals: Yalcin 25, 29.

Attendance: 32,957

Referee: Lucilio Cardoso Cortez Batista (Portugal).