Martin Odegaard's clinical finish secured Arsenal a hard-earned 1-0 victory over Napoli in their UEFA Champions League league phase opener at the Diego Armando Maradona Stadium on Wednesday.

The Gunners dominated the contest from start to finish, amassing 26 shots with an extraordinary 4.05 expected goals — yet a succession of missed chances threatened to leave them without reward before Odegaard finally broke the deadlock.

Chances spurned before the breakthrough

Mikel Merino and Bukayo Saka both wasted clear opportunities in the first half, while Piero Hincapie blazed over from close range after the interval. Mikel Arteta's side were ruthless in their approach play but struggled to find the finishing touch for large stretches of the evening.

The opener arrived when Odegaard drove a low shot off the post and into the net following a sharp one-two with substitute Christos Tzolis — the Norwegian's fourth goal in five appearances this season.

Late drama fails to deny Arsenal

The lead could have been extended immediately, but substitute Noni Madueke missed a one-on-one, and Tzolis's follow-up was cleared off the line, handing Arsenal an uncomfortable final few minutes.

Napoli's best opening fell to former Manchester City playmaker Kevin De Bruyne, who chose to cross rather than shoot when put clean through on goal. It was a decision that allowed Arsenal to hold on and celebrate a winning start to their European campaign.

The result is Arsenal's fifth consecutive victory in all competitions this season, and it confirms that last season's UEFA Champions League runners-up are once again a serious force in Europe's premier club competition.