Many reasons have been attributed to Manchester City already reaching the Champions League knockout rounds for the first time in their history. A less hostile group, the arrival of Manuel Pellegrini and even a more experienced squad are possible explanations. But the reinvigorated Samir Nasri has perhaps been overlooked.
From the sulking Frenchman who had such a miserable season both in Europe and domestically in 2012/13 in the wake of being disciplined by his country's Football Federation at Euro 2012, before also experiencing a bust-up with former City boss Roberto Mancini, the 26-year-old now looks close to being back to his best.
Nasri is darting around midfield, drifting in from wide areas to make the play and producing killer passes and assists for team-mates Sergio Aguero and Alvaro Negredo. It is reminding everyone he is still the player who led City to pay Arsenal a transfer fee of £24million in the summer of 2011.
The former Marseille man still has some way to go to again win over his critics in France, particularly given his poor performance as a first-team starter in the first-leg defeat by Ukraine in their World Cup play-off - which led to him being dropped to an unused substitute for Les Bleus' famous second-leg fightback. But, ahead of Wednesday's Champions League meeting with Viktoria Plzen in Group D at Etihad Stadium, he is certainly impressing again with City.
Pellegrini said recently of Nasri: "He is a player who has great technical quality and he works in the game a lot - not only in the last 25 metres. He runs back and makes passes. He is a very creative player."
It is Pellegrini, a summer successor to the often impersonal Mancini, who has been vital in turning around Nasri's slump. Nasri has previously admitted as much, comparing Pellegrini to his former Arsenal boss - Arsene Wenger, and saying of his current City manager: "I feel that he trusts me and that he gives me responsibilities on the pitch. When you have a manager like that, you want to repay that sort of faith - and that is what I am trying to do."
Nasri of course deserved criticism for becoming distracted in the wake of his personal problems and frustrations at Euro 2012, which had seen him hit with a three-match ban from his national team having sworn at a reporter following France's quarter-final defeat by Spain. He had earlier in the tournament also held a finger over his mouth and yelled, 'shut your mouth' at another journalist after scoring in France's opening match against England. Likewise, Nasri, or any professional of note, should have been able to find a working relationship with Mancini.
But Nasri also deserves credit for again getting his career back on track this season. He said recently of his problems since Euro 2012: "Emotionally, I went through several moments of doubt and reassessment. Some of the criticism I got hurt me, and lots of bad things were said. I accept criticism as long as it is justified but there were lots of lies about me. I made mistakes, I know, but I am not the ugly duckling that some people seem to think."
And it is in the Champions League where Nasri has been especially impressive, providing a main reason why City have already qualified for the last 16 with two games to spare. He was far from the only City player to have a wretched game when they were outclassed by Bayern Munich on Matchday Two at the beginning of October but he has otherwise been superb in Europe.
Nasri has assisted four of City's 11 goals. Before Matchday five, that put him joint top with Real Madrid's Angel di Maria in terms of the highest number of assists by midfielders in this season's Champions League. Including those assists, Nasri has created 10 goalscoring chances for team-mates. That total by a midfielder was the same as four other players, including Arsenal's Mesut Ozil and Barcelona's Andres Iniesta, and was only bettered by Juventus' Andrea Pirlo (11) and Bayern winger Franck Ribery (15).
Not only that but Nasri's passing accuracy in the opposition half (89.6 per cent) is the best of any of City's midfielders. His work-rate, which Pellegrini referenced, for the team has been also been impressive. He has covered 31579 metres in his 248 minutes on the pitch, competing in 21 duels in that time and winning 12 - which is three more than City team-mate David Silva from the same amount of attempts.
This all reflects a player in form. As City look to finish the group strongly against Plzen on Wednesday and then at Bayern on 10th December before the winter break, Nasri will remain a key man.
Man City v Plzen is live on Sky Sports 4HD on Wednesday from 7.30pm
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