Chelsea kept up their 100% record in Europe this season as Jose Mourinho's side beat his former club Porto.
Alexei Smertin gave Chelsea an early lead with a crisply executed volley after some slick approach play.
And a Didier Drogba header from a Damien Duff free-kick doubled Chelsea's advantage soon after the interval.
The European champions then briefly unnerved Chelsea when Benni McCarthy lashed the ball home before John Terry's header made the game safe.
Porto were unrecognisable from the team that won last season's final under Mourinho, with only five players of the side that beat Monaco starting the game on Wednesday.
Diego, brought from Santos to replace the Barcelona-bound Deco, gamely battled to provide impetus for Porto in midfield as did Ricardo Quaresma on the wings.
Those two youngsters did their best to make the most of the possession Porto enjoyed, but the visitors' attacks tended to peter out on the edge of the Chelsea box.
So much so that Cech did not have to make his first serious save until midway through the second half when he got down quickly to hold a McCarthy shot.
However McCarthy did not have to wait long to get on the scoresheet, the Porto striker lashing the ball home after Cech could only punch a long-range Carlos Alberto shot into the South African's path.
Chelsea had made an edgy start to the game though the slick way Eidur Gudjohnsen, Damien Duff and Smertin combined to give Mourinho's side the lead helped banish their early nerves.
Duff's sublime flick over Jorge Costa sent Gudjohnsen clear and the Icelandic international swept the ball back across goal.
Demonstrating superb technique, Smertin volleyed low and hard past Vitor Baia into the corner to claim his first Chelsea goal.
Duff and Gudjohnsen then opened up the left flank of the Porto defence and from the Icelandic striker's cross Drogba went close with an acrobatic volley.
More good work from Gudjohnsen then released Duff, but the Irishman was unable to slip the attentions of Jose Bosingwa.
It was from a Duff free-kick that Chelsea extended their lead.
The Irishman flighted the ball into the box and Drogba, with his back to goal, headed past Baia.
Chelsea continued to unsettle Porto from set pieces and two minutes after McCarthy's goal, Terry's bravery restored the home side's two-goal advantage.
This time Lampard provided the delivery and Terry launched himself at the ball to crash a header past Baia.
Drogba then got on the end of another Lampard free-kick, but his goal was ruled out for offside.
Chelsea: Cech, Paulo Ferreira, Ricardo Carvalho, Terry, Gallas,
Smertin, Makelele, Lampard, Duff (Tiago 66),
Gudjohnsen (Kezman 80), Drogba.
Subs Not Used: Cudicini, Johnson, Cole, Geremi, Huth.
Booked: Gallas, Ricardo Carvalho, Smertin.
Goals: Smertin 7, Drogba 50, Terry 70.
FC Porto: Vitor Baia, Bosingwa, Pepe, Jorge Costa,
Ricardo Costa, Derlei (Postiga 80), Maniche, Diego, Costinha,
Quaresma (Carlos Alberto 58), Luis Fabiano (McCarthy 57).
Subs Not Used: Nuno, Pedro Emanuel, Leal, Areias.
Booked: Luis Fabiano, Derlei, Pepe.
Goals: McCarthy 68.
Ref: Herbert Fandel (Germany).