London - After suffering the ignominy of an early exit from the Champions League as defending champion, Chelsea began its quest to win the Europa League by beating Sparta Prague on Thursday.
Oscar scored late to give the London side a 1-0 victory - and a valuable away goal - in the first leg of the last-32 match.
His strike made up for another bad night for striker Fernando Torres, who has scored just one goal in 13 games.
"We have to create more opportunities and the strikers will score more goals," Chelsea manager Rafa Benitez said. "(Torres') work rate on Thursday was really good and thanks to him the rest of the team, especially the second line of offensive players, they could create."
But there was only gloom for the team Benitez won the Champions League title with in 2005.
Liverpool, the five-time European Cup champions, lost 2-0 at Zenit St. Petersburg.
Premier League rival Tottenham will take a 2-1 lead to Lyon next Thursday after Gareth Bale scored twice from free kicks, while Inter Milan won 2-0 at home against Cluj thanks to Rodrigo Palacio's double.
In the Czech capital, Chelsea's breakthrough came after Benitez replaced Juan Mata with Oscar. The Brazilian's first involvement in the match ended with a goal in the 82nd minute after playing a one-two with Eden Hazard.
"(The players) have to realise it's an opportunity to win a trophy," he said. "I'm sure if we can progress they will see the option."
Winning the Europa League would restore some pride at Chelsea after it became the first Champions League winners to exit the competition in the group stage.
Chelsea is already out of the League Cup, faces an FA Cup fourth-round replay against third-tier club Brentford on Sunday, and looks like finishing no higher than third in the Premier League.
Tottenham, which is only a point behind Chelsea in the Premier League, also took a one-goal first-leg advantage, albeit at home with a difficult return fixture to come in Lyon.
Bale fired Tottenham in front in first-half stoppage time directly from a 35-meter free kick in which the ball dipped over the defensive wall into the net.
That goal, however, was surpassed by the brilliance of Lyon's leveler.
Samuel Umtiti seized upon a headed clearance and unleashed a first-time half-volley from the edge of the penalty area that swerved past goalkeeper Brad Friedel into the top corner.
But another free kick at the end of the second half was expertly dispatched by Bale again into the net.
While Tottenham's priority is finishing in the Premier League's top four to secure Champions League football next season, Liverpool's focus is squarely on this season's Europa League.
A full-strength Liverpool team conceded two goals in two minutes in Moscow from the 70th with Hulk and Sergei Semak scoring, leaving the Reds with a difficult task in the return leg at Anfield.
Another Russian team, Rubin Kazan, won by the same score line to stun defending champion Atletico Madrid. Goals from Gokdeniz Karadeniz and Pablo Orbaiz ended a 21-match winning streak at the Vicente Calderon for Atletico.
Bayer Leverkusen conceded at home for the first time in Europe this season, with Oscar Cardozo's second-half strike giving Benfica a 1-0 win in Germany.
Another German side, Hannover, was beaten 3-1 by Anzhi Makhachkala, with the free-spending Russians recovering from conceding the opener and responding with goals from Samuel Eto'o, Odil Ahmedov and Mbark Boussoufa.
The highest-scoring game of the night was Borussia Monchengladbach's 3-3 draw against Lazio with three penalties awarded. Only the first and third were scored - by Martin Stranzl and Thorben Marx - with Stranzl missing his second.
The teams in the strongest position to advance are Levante and Viktoria Plzen, who both won their first legs 3-0.
Plzen stunned Napoli with a surprisingly comfortable win at the Serie A title chasers, with Vladimar Darida, Stanislav Tecl and Frantisek Rajtoral scoring for Czechs.
Pedro Rios, Jose Barkero and Obafemi Martins scored for Levante at home against Olympiakos, turning around its form after losing five of its past six domestic matches in Spain.
In Belarus, Fenerbahce held on for a 0-0 draw at BATE Borisov despite playing with 10 men from the third minute after Raul Meireles was sent off for hacking Alexander Hleb from behind.
It was also scoreless between Newcastle and Metalist Kharkiv after Papiss Cisse had two goals for the English hosts disallowed for offside.
There was also a draw in the Ukrainian capital where Dynamo Kiev was held 1-1 by Bordeaux after Lukman Haruna's opener for the hosts was canceled out by Ludovic Obraniak.
In other results on Valentine's Day, Valentin Stocker scored Basel's first in a 2-0 victory over Dnipro, Ajax beat Steaua Bucharest by the same score, and Genk drew 1-1 at Stuggart.