David Luiz's last-gasp free-kick earned Chelsea a 2-1 victory over Basle in the Europa League semi-final first leg at St Jakob Park.
Last season's Champions League winners went in front when Branislav Ivanovic - victim of Luis Suarez's bite - won a header which went in off Victor Moses, who claimed his third goal in as many Europa League games.
The visitors should have scored again prior to Fernando Torres striking the post before Cesar Azpilicueta was adjudged to have fouled Valentin Stocker and Fabian Schar converted an 87th-minute penalty. However, Chelsea responded and Luiz's late intervention earned the advantage ahead of next week's return at Stamford Bridge.
Chelsea, who had lost four of their five prior European away games, missed numerous chances and Luiz's shot skipped around the wall and inside the post after John Terry had been denied by goalkeeper Yann Sommer's point-blank save earlier in stoppage time.
Basle eliminated Zenit St Petersburg and Tottenham and Rafael Benitez was taking few chances in Switzerland. Left-back Ashley Cole returned from a hamstring injury and Terry's recall in defence saw Luiz move into midfield alongside Frank Lampard.
Chelsea, playing in white, had to be patient as Basle started well before Azpilicueta raced down the right and crossed to the near post, where Lampard's prod towards goal was turned away for a corner by Sommer. Lampard's set-piece was met by Ivanovic, whose header deflected off Moses and bounced inside the far post.
Eden Hazard, playing centrally behind Torres, was doing his utmost to find openings in the Basle defence, but all too frequently Chelsea gave the ball away. Torres twice had half-chances before Lampard found Ramires and the Brazilian's dipping shot from the right was saved well by Sommer.
Much of the second half was disjointed and punctuated by mistakes as Chelsea were forced to repel repeated Basle attacks. Fabian Frei shot narrowly wide from the edge of the box and Cole received a yellow card for time wasting at a throw-in before Aleksandar Dragovic was booked for a sliding challenge on Torres, meaning the defender will now miss the second leg.
Hazard made way for Juan Mata and Lampard was replaced by Oscar as Chelsea's search for a second continued to prove elusive. Basle substitute Marcelo Diaz curled an effort narrowly wide and Cech collected at the feet of Mohamed Salah after the winger had been played in by Dragovic. But Chelsea found themselves level when Azpilicueta was ruled to have hauled down Stocker in the area and Schar sent the ball down the middle of Cech's goal.
Oscar shot narrowly wide and Terry's header was somehow stopped by Sommer before Luiz took his chance from 25 yards to belatedly give Chelsea the advantage in the tie.