Anderlecht hold a narrow advantage over Slavia Prague in their Champions League qualifier after failing to make the most of a good performance on home soil.
The Belgians attacked from the opening moments with Bart Goor putting an effort just over and Hannu Tihinen being denied by goalkeeper Matus Kozacik.
But it took just six minutes for them to make the breakthrough as Goor latched on to Par Zetterberg's long through ball and beat the offside trap to slide a low shot into the corner of the goal.
Slavia tried to respond immediately, and Stanislav Vlcek saw a header saved by goalkeeper Daniel Zitka before Patrik Gedeon fired just wide.
They found an equaliser in the 21st minute. Marek Suchy played a smart pass into Lukas Jarolim who had time to size up his options before launching a lob over the head of Zitka and into the net.
Jarolim also had a hand in the next goal 17 minutes later, but unfortunately for him and his team it came at the other end.
His foul on Zetterberg right on the edge of the penalty area allowed Goor to float a free-kick onto the head of Mbo Mpenza and he planted a header low into the corner of the net.
Anderlecht continued to push forward after the break, with Kozacik stretching to keep out Goor's low driven shot, but Slavia looked dangerous on the counter attack and Stanislav Vlcek was inches away from an equaliser when his effort from the edge of the area went the wrong side of the post.
Anderlecht coach Franky Vercauteren introduced Christian Wilhelmsson and Walter Baseggio in the final stages of the game, looking to establish a two-goal cushion, and it almost came in the final minute of the game.
Ivan Kovac slipped, allowed Serhat Akin a shot on goal, but he fired wide and the Belgians were forced to settle for a 2-1 scoreline ahead of the second leg.
Goals: 7' Goor 1-0, 21' Jarolim 1-1, 38' Mpenza 2-1
Anderlecht: Zitka, Vanden Borre, Kompany, Tihinen, Deschacht, Vanderhaeghe, Zetterberg (81' Baseggio), Goor, Jestrovic (62' Wilhelmsson), Mpenza, Serhat
Slavia Prague: Kozacik, Kovac, Latka, Holenak, Zboncak, Pitak (90' Zabojnik), Gedeon, Jarolim, Suchy, Hrdlicka (46' Svento), Vlcek (84' Pesir)
Referee: Baskabov (Rus)