Substitute Miroslav Klose struck a minute from time to earn FC Bayern München a narrow lead against ACF Fiorentina as the German hosts' 13th successive win proved unlucky for the brave visitors.
An Arjen Robben penalty in the dying seconds of the first half had eased Bayern in front but Per Krøldrup, whose tackle had brought the spot-kick, deservedly equalised five minutes after the break. The Italian side looked set for a firm foothold in the first knockout round tie despite Massimo Gobbi's 73rd-minute red card, yet Klose's close-range header means it is advantage Bayern ahead of the second leg on 9 March.
Fiorentina have laboured of late, but arrived in Bavaria on the back of five consecutive UEFA Champions League wins and they matched their hosts in a keenly-contested opening. A raking ball aimed towards Robben from kick-off had shown Bayern's intent, but the visitors were just as positive. Neat build-up play gave Marco Marchionni an opening before miscommunication between Daniel Van Buyten and Hans-Jörg Butt almost allowed Alberto Gilardino to steal in.
At the other end Mario Gómez forced Sébastien Frey into a near-post save, yet Fiorentina proved the more enterprising. Gilardino would surely have tested Butt after he had raced clear only for a slip to give Holger Badstuber the chance to recover ground. Irresistible in the Bundesliga, Bayern were fractious – Franck Ribéry's shot from distance, though well-struck and equally well-saved by Frey, evidence of the hosts' inability to fluster a disciplined rearguard.
Set-pieces can provide relief in such situations, and Martín Demichelis headed narrowly over, but it was Robben's vaunted fleet of foot that helped break the deadlock. Surging forward, the Dutchman slipped a pass into Ribéry's path. Clean through, the Frenchman was sent tumbling by Krøldrup, allowing Robben to claim his sixth goal in as many games with a convincing finish from the spot.
The injured Van Buyten failed to emerge after half-time, and he was sorely missed as Bayern's advantage was quickly cancelled out. Marchionni's corner was allowed to travel deep into the box, and when the ball ricocheted off Stevan Jovetić, Krøldrup reacted smartly to squeeze a shot past Butt.
With Ribéry out of sorts in his first appearance in the competition since Matchday 2, the burden of invention fell on Robben – he did not shy away. A piercing burst down the left again opened up the Viola back line, but when he cut the ball back, it rolled harmlessly across the face of Frey's goal.
It was a clumsy challenge on the ex-Chelsea and Real Madrid CF man that saw Gobbi dismissed, but Bayern's fluidity of recent weeks was conspicuously absent. Klose's opportunism, though, finally undid Fiorentina. Frey parried Ribéry's shot into the path of Ivica Olić, whose header across goal dropped perfectly for Klose to nod home. There was still time for Robben to test Frey again as the Viola retained ambitions of reaching the quarter-finals for the first time.