Who has been the most important player so far for each of this season's UEFA Champions League semi-finalists?
Let's start with Tuesday's tie, from which we have full match commentary on our UEFA.com panel show Matchday Live, as FC Barcelona travel to FC Bayern Munchen.
The new Bundesliga champions haven't been nearly as reliant on the firepower of Mario Gomez this season. He struck 12 times in the 2011/12 UEFA Champions League but injury and the excellent form of Mario Mandžukić have restricted his chances. Bastian Schweinsteiger and Javi Martínez have formed an excellent central midfield partnership but for me Thomas Müller has been pivotal in Europe this term.
The German international seems to get his goals in key games, and while his strike against Chelsea FC in last year's final couldn't help Bayern win it, he found the net in the crucial matchday five encounter with Valencia CF and against both Arsenal FC and Juventus in the knockout rounds.
With Barcelona it is always hard to look past Lionel Messi with his eight goals in ten outings – his absence was certainly felt for the first hour of the quarter-final second leg with Paris Saint-Germain FC. I feel Jordi Alba deserves an honourable mention for his seamless transition into the Blaugrana's back four and his ability to pop up at the other end of the pitch to help his team-mates – witness his late strikes against Celtic FC and AC Milan. But no player has made more passes than Xavi Hernández in this season's competition (1,143 if you're asking) and he remains as crucial as ever to Tito Vilanova's side. He gets my vote.
Wednesday's semi-final commentary on Matchday Live, meanwhile, features Borussia Dortmund hosting Real Madrid CF for the second time this campaign.
BVB are the only unbeaten team left in the tournament and their four points picked up against José Mourinho's side in the group stage might have been six but for a late Madrid equaliser at the Santiago Bernabéu. For me, while Robert Lewandowksi is their top scorer, Marco Reus has been their outstanding performer in the UEFA Champions League.
With four goals in his first term in the competition, he has netted at the Amsterdam ArenA, City of Manchester Stadium and Bernabéu. His late strike against Málaga CF last time out helped spark the dramatic turnaround in the quarter-final, and his pace and capacity to drive play forward have helped change Dortmund's dynamic into one more suited to continental football.
Finally for Real Madrid there's little doubt in my mind that Cristiano Ronaldo has been their star man once again. Among his 11 goals in ten matches, he scored at the BVB Stadion earlier in the campaign, while popping up with two against former club Manchester United FC in the round of 16. The leading marksman in the 2012/13 UEFA Champions League is keen to share the plaudits with his colleagues and manager, yet he could be the one to fire them to that tenth European Cup.
So Müller, Xavi, Reus and Ronaldo are my picks, but what do you think? Leave your comments below or tweet us on the show @championsleague using #matchdaylive.
European football expert Andy Brassell guests on the panel show on Tuesday and Wednesday. Join us on UEFA.com from 19.30CET on both nights for the best build-up and full match commentary of our two UEFA Champions League semi-final first legs.
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