LEVERKUSEN, GERMANY - Bayer Leverkusen have one foot in the Champions League's quarter-finals following their shock 1-0 home win over last season's finalists Atletico Madrid, who finished with ten men on Wednesday.
Atletico Madrid's French forward Antoine Griezmann and Leverkusen's Bosnian defender Emir Spahic (R) vie for the ball during their UEFA Champions League first-leg, round of 16 football match in Leverkusen, Germany on February 25, 2015
Hakan Calhanoglu's superb second-half goal in the last 16, first-leg clash means Bayer take a slender advantage to Atletico's Vicente Calderon Stadium for the return leg on March 17.
"I think we were clearly the better team and therefore we deserved the win," said match-winner Calhanoglu.
"I gave it all I had for the goal, but we have to play just as well in the return leg as we did today and then we have a good chance."
Reigning Spanish league champions Atletico played the last quarter of an hour with ten men after defensive midfielder Tiago was sent off for a second booking.
"The result makes things tough for the second half, but we still have a chance," said Atletico captain Gabi.
Bayer, the 2002 Champions League finalists, edge closer to breaking their last 16 jinx having failed to pass this stage of the competition in their last three previous attempts.
Roger Schmidt's Leverkusen ended their three-match winless streak in the Bundesliga in style by stunning the 2014 finalists.
Having been humiliated 4-0 at home by Paris Saint Germain last season at the same stage in the competition, Leverkusen produced a spirited performance.
Their potent pressing game nullified the threat of Atletico striker Mario Mandzukic and attacking midfielder Antoine Griezmann, who have scored 37 goals between them this season.
The hosts controlled the early stages as Mandzukic found himself in the unusual position of clearing a 12th-minute shot off the line from Leverkusen centre-back Emir Spahic.
The Bosnia captain then rattled the top-left corner of the goal post with a long-range strike on 26 minutes with Atletico goalkeeper Miguel Angel Moya beaten.
Madrid's best chance of the first-half came when Juanfran's shot was blocked and Leverkusen goalkeeper Bernd Leno out-jumped the waiting Griezmann to deny the Frenchman an easy header right in front of goal on 39 minutes.
Atletico coach Diego Simeone was forced into two changes before the break as both right winger Saul Niguez and right-back Guilherme Siqueira came off injured.
Leno kept Atletico out with a superb diving reflex save to deny Tiago at close range just before the half-time whistle -- which ex-Germany goalkeeper Oliver Kahn described as "world-class".
Leverkusen took the lead when Germany winger Karim Bellarabi cut across the face of the goal, then his back-heeled pass found Turkey international Calhanoglu, who blasted his shot past Moya from a tight angle on 57 minutes.
Simeone brought on Spain's ex-Liverpool and Chelsea striker Fernando Torres for the final 25 minutes in a bid to get Atletico a crucial away goal.
Having already been booked early in the first-half, Tiago's dismissal for his second yellow gave Leverkusen the numerical advantage, but Atletico kept up the pressure as Leno endured a busy final 20 minutes.