LONDON - Last year’s Champions League hero could return to the competition after his unhappy foray in the Far East while two of its oldest foes meet again in this week’s last-16 first leg ties.Didier Drogba, who took the winning penalty for Chelsea in last season’s final, scored five minutes into his Galatasaray debut on Friday and could enter the fray along with newly-signed Dutch playmaker Wesley Sneijder against Schalke 04 on Wednesday.Seven-time European champions AC Milan and Barcelona, who met in both the group stage and quarterfinals last season, face off again at the San Siro with the Lionel Messi-inspired Catalans hot favourites to pull off another win.Arsenal, who have reached this stage for the 13th time in a row, host a rampant Bayern Munich while Porto host impressive debutants Malaga in a match which features so many South Americans it resembles a Libertadores Cup tie.Milan’s meeting with Barcelona is the pick of the ties although the Serie A side will not be able to field Mario Balotelli who has scored four goals in three games since his move from Manchester City.The maverick striker is ineligible for Wednesday’s match at San Siro, having played for the English side in the group stage when they were eliminated.Contrasting fortunesArsenal were beaten by second-tier Blackburn Rovers in the FA Cup on Saturday and their up-and-down form is in complete contrast to Bayern, who have won their five Bundesliga matches since the winter break without conceding a goal.With a massive 15-point lead over Borussia Dortmund, the Bavarians can concentrate their efforts on the Champions League, where they have finished runners-up twice in the last three seasons.For Arsenal, who lost at this stage in each of the last two seasons, the Champions League appears to be their only hope of avoiding another trophyless season.Galatasaray’s recent acquisitions could give an added edge to a team famous for their fanatical home crowd as they attempt to become the first Turkish side to reach the last eight since Fenerbahce five years ago.The Turkish league leaders face a Schalke side in freefall after winning only one out of five league games since the winter break following the sacking of Huub Stevens and his replacement with Jens Keller.Drogba, 34, who scored the equalising goal for Chelsea as they drew 1-1 with Bayern in last year’s final before netting the decisive penalty, moved to Shanghai Shenhua after that but cut short his stay in China amid reports of unpaid wages.Sneijder joined the Turkish club from Inter Milan, the side where he won the title in 2010.Porto’s match at home to Malaga on Tuesday features a host of players with South American international experience.The Portuguese side regularly field seven or eight South Americans in their starting line-up while their opponents, who have already exceeded expectations in their debut season, are led by Chilean coach Manuel Pellegrini.