Hosts Porto and Bayern Munich were made to work as they recorded respective 2-1 wins over Arsenal and Fiorentina in the first legs of their UEFA Champions League Round of 16 matches.

With such narrow margins to defend in the return legs in three weeks time, the Portuguese and German sides know they still have much to do to advance to the quarter-finals.

The results
Porto 2-1 Arsenal
Goals: Silvestre Varela 11, Falcao 51 (Porto); Sol Campbell 19 (Arsenal)

Bayern Munich 2-1 Fiorentina
Goals: Arjen Robben 45 pen, Miroslav Klose 89 (Bayern Munich); Per Kroldrup 50 (Fiorentina)

Goal of the night
Porto 2-1 Arsenal (Falcao 51)

Shepherding the ball back to the box under no real pressure, Sol Campbell nudged it towards goalkeeper Lukasz Fabianski, who picked it up, giving away an indirect free-kick in the process. While the Gunners protested the decision, Ruben Micael stole in to take the kick quickly, teeing up Falcao to put Porto back in front with the easiest of goals.

The key moments
The lone Englishman: Shorn of several first-team players (Andrei Arshavin, Robin van Persie, Eduardo, Alex Song, William Gallas, and Manuel Almunia), Arsenal struggled to find their bearings during a torrid opening. Fabianski was at fault as he inadvertently pushed Silvestre Varela's low cross over his line to hand Porto the perfect start. The Londoners came up with an instant riposte, however, Sol Campbell nodding in after Tomas Rosicky had headed Thomas Vermaelen’s flick-on into his path, the kind of goal Arsenal were once famed for.

The adventures of Per Kroldrup: Fiorentina’s 31-year-old Danish defender had a bittersweet evening at the Allianz Arena. His foul on Franck Ribery on the stroke of half-time resulted in a penalty that was expertly dispatched by Arjen Robben. Six minutes after the restart Kroldrup was smiling again. Popping up at the far post after Stevan Jovetic had nudged on Marco Marchionni’s corner, he swept the ball past Hans-Jorg Butt in the Bayern goal. Having atoned for his first-half blunder, the experienced Dane could return to his central-defensive duties with his conscience clear.

Old heads come good: With an hour gone and his side drawing 1-1 with La Viola, Bayern coach Louis van Gaal opted for experience, sending on Ivica Olic and the indefatigable Miroslav Klose for Mario Gomez and Thomas Muller. And after the Italians had been reduced to ten men, Klose showed exactly why he had been thrown into the fray. Just a minute remained when Robben sent in a stinging shot that Fiorentina keeper Sebastien Frey could not hold on to. First to react, Olic nodded the loose ball to the unmarked Klose, who ignored Italian pleas for offside to head home and secure Bayern’s 13th consecutive win in all competitions.

FIFA World Cup™ contenders
French flyer Franck Ribery is back in form after his recent injury problems and should be fresh for South Africa 2010. His Dutch partner Arjen Robben provided the perfect foil for him and was once again Bayern’s man of the match with another inspired performance. Although he ended up on the losing side, Fiorentina striker Alberto Gilardino showed his worth with some valuable contributions at dead-ball situations, both in attack and defence.

A severely weakened Arsenal side stayed in contention in their tie with Porto thanks in no small part to the unstinting work of Cesc Fabregas in midfield, while the central-defensive partnership of Bruno Alves and Rolando helped the hosts keep their shape.

Next matches
Round of 16 first leg - Tuesday 23 February (second legs to be held 17 March)

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