It seems strange to relate after Arsenal’s biggest away win in Europe for five years, but Arsène Wenger had almost as much to be concerned about on the long flight home last night. If not quite a game of two halves, this Champions League tie certainly contained wildly contrasting performances.

As an optimist, the Arsenal manager will undoubtedly look on the bright side, preferring to savour the passing of Cesc Fàbregas and finishing of Theo Walcott rather than lament the space that his side allowed their opponents in midfield or fret over the glaring deficiencies of Alexandre Song and Mikaël Silvestre as a central-defensive pairing. But a quick look at the match video this morning could alter his perspective. The tone of a crazy match that could have ended with both sides scoring in double figures is best conveyed in that Manuel Almunia was Arsenal’s best performer.

The North London side’s usual style of play is a quick-tempo game based on passing triangles of dizzying beauty, but this rout was based on taking a more direct route to goal. Precise passes they may have been, but all three of their first-half goals game from straight-as-a-die balls through the middle.

The first two were provided by Fàbregas, who appeared to be revelling in the freedom afforded by a deeper-lying role to demonstrate a range of delivery more commonly seen in American football. As chance would have it, the New Orleans Saints will spend the next few days at Arsenal’s training ground in preparation for Sunday’s National Football League match against the San Diego Chargers at Wembley and Drew Brees, their quarterback, could do worse than ask Fàbregas for advice. The midfield player will have enjoyed showcasing his full range of skills to Luis Aragonés, the Fenerbahçe and former Spain coach, who did not start him in a match of significance until the final of Euro 2008 this summer, but the Spaniard could not fail to have been impressed last night.

Emmanuel Adebayor blasted a chance created by Fàbregas over the bar in the fifth minute, but the Togo striker treated such first-class service with greater respect five minutes later, running on to a low through-ball to shoot past Volkan Demirel.

Walcott had done well to stay out of the way while in an offside position and he was even more directly involved 70 seconds later to profit from another eye-of-the-needle ball from Fàbregas. The 19-year-old’s finish was even more impressive than that of his team-mate, showing great speed to beat Volkan to the ball and finding the back of the net from an acute angle on the right.

Arsenal should have been able to celebrate a victory that all but guaranteed their progress to the first knockout round at that point, but the visiting team’s defending was as clumsy as their attacking was classy. Almunia had already been required to make a point-blank save from Ugur Boral in the fourth minute and for the rest of the first half he was by far the busier goalkeeper. The Spaniard dived bravely at the feet of Semih Sentürk in the fifteenth minute, suffering a cut on the head for his trouble, but he was helpless four minutes later when Daniel Güiza’s volley was deflected past him by Silvestre.

Arsenal soon extended their lead again with the fourth goal in 12 breathless minutes as Abou Diaby bundled Edu off the ball to shoot past Volkan, but Wenger’s mood on the bench remained agitated, for good reason. Silvestre and Song had previously played together in the heart of defence for only 45 minutes — and it showed. The pedestrian Silvestre, in particular, looked vulnerable to the pace of Güiza, who broke through twice just before half-time and, without smart saves from Almunia, the home side could even have gone in on level terms.

Song partially atoned for his own errors by scoring with a crisp volley in the 50th minute, but still Arsenal were unable to close out the game. Almunia again denied Güiza on the edge of box and Emmanuel Eboué cleared off the line from Edu before Güiza finally got the goal he deserved in the 79th minute. Aaron Ramsey, a substitute, scored his first goal for Arsenal from the edge of the area in stoppage time.

Wenger’s celebratory glass of wine will have remained half-full as he flew back to London, but only just.

Fenerbahçe (4-3-1-2): Volkan Demirel — Gökhan Gönül (sub: Burak Yilmaz, 79min), Edu, Lugano, Roberto Carlos — C Maldonado (sub: Ali Bilgin, 52), Selçuk Sahin, Ugur Boral — Alex — D Güiza, Semih Sentürk. Substitutes not used: Volkan Babacan, Josico, Gürhan Gürsoy, Ilhan Parlak, Yasin Çakmak. Booked: Lugano, Selçuk Sahin, Semih Sentürk.

Arsenal (4-4-1-1): M Almunia — E Eboué, A Song, M Silvestre, G Clichy — T Walcott (sub: J Djourou, 84), F Fàbregas, Denilson, A Diaby (sub: A Ramsey, 73) — S Nasri — E Adebayor (sub: C Vela, 86). Substitutes not used: L Fabianski, R van Persie, N Bendtner, K Gibbs. Booked: Diaby, Song.

Referee: P Fröjdfeldt (Sweden).