Chelsea will take a 1-0 lead home for the second leg of the Champions League quarterfinals against Benfica after Salomon Kalou's second-half goal gave his team its first away win in the competition this season.
Kalou tapped in Fernando Torres' cross from the right in the 75th minute of the first leg to give Chelsea the advantage ahead of the Stamford Bridge match on April 4.
The lone English club left in the tournament managed only half the number of Benfica's 22 attempts on goal at the Stadium of Light and scored against the run of play.
Chelsea was coming off a 2-1 loss at Manchester City last week and a 0-0 home draw with Tottenham, and the team defended well but created few chances in Lisbon other than Juan Mata hitting the post from a wide angle in the 61st after a defensive blunder.
Chelsea is fifth in the Premier League, outside the automatic qualification places for next season's elite European club tournament. That means it may need to win the trophy this year to get back into the competition.
It was the first loss in 11 European home games for Benfica, which is aiming to make its first semifinal appearance in the tournament in 22 years.
The Portuguese club drew home and away against Manchester United in the group stage on its way to its first quarterfinal appearance in six years.
Roberto Di Matteo recalled Fernando Torres and David Luiz on Tuesday in place of Didier Drogba and Gary Cahill, who both started against Tottenham last weekend. Frank Lampard was also on the bench.
Benfica made most of the running, with Chelsea mostly content to slow the pace.
Benfica striker Oscar Cardozo rose above two defenders but headed weakly at goalkeeper Petr Cech in the 15th. He soon had a better opening, running into the area and receiving the ball on his chest before hitting a volley wide.
Benfica lacked composure in front of goal, with Bruno Cesar's 32nd-minute shot the first on target.
Ramires, a former Benfica player, kept outpacing left back Emerson, but Torres - who recently ended a career-worst goal drought of 26 games - couldn't convert the possession he received into clear chances.
Midfielder Raul Meireles' low drive just before the interval forced goalkeeper Artur to dive sharply to his right in Chelsea's best first-half effort.
Benfica cranked up the pressure after the break. Cardozo's close-range shot looked to be going in but it hit Luiz on the chest, and Jardel's header forced a reflex save from Cech.
Chelsea captain John Terry was repeatedly called into action, blocking Alex Witsel's shot then cutting out Rodrigo's pass to Cardozo that would have put him through on Cech. Lampard came on for Meireles, but Chelsea still looked the less likely victor.
But when Torres beat Jardel on the right flank, Kalou just needed to side-foot the ball into the net for the winner.
