Arsenal are succumbing to a 2-1 defeat at the hands of Olympiacos in Tuesday night's Champions League Group F clash at the Emirates Stadium.

Following a tentative start in North London, the hosts were first to threaten as Theo Walcott beat the offside trap seven minutes in and sent a short cross into space, but defender Alberto Botia was able to clear.

Three minutes later the Gunners managed to repel an Olympiacos free kick before launching a counter-attack which saw Walcott fire straight at opposition goalkeeper Roberto.

The visitors slowly grew into the game as, 22 minutes in, Pajtim Kasami skinned past Francis Coquelin and picked out Konstantinos Fortounis on the edge of the box, but the resulting shot sailed wide of David Ospina's left-hand post.

Arsenal began to struggle against their opponents and, just after the half-hour mark, found themselves a goal down when Felipe Pardo's effort at the edge of the hosts' box took a deflection off Alex Oxlade-Chamberlain and wrongfooted Ospina en route to the back of the net.

It didn't take long for Arsene Wenger's side to pull level, however, just three minutes elapsing before Alexis Sanchez marauded down the right before cutting back to Walcott, who showed great composure inside the box to rifle home.

Nevertheless Olympiacos would go on to end the half in the lead as, just five minutes before the break, Fortounis's corner was spilled by Ospina and, as he attempted to gather it, crossed the goalline.