The home side, who have struggled throughout the defence of their Asian title, needed a first win of the campaign to retain hope of qualifying for the last 16 and the pressure showed in the early exchanges.

Al Rayyan’s Thiago Mendes wasted an opportunity when Khaled Eisa’s poor clearance landed at the feet of Guedes and, after the former Shandong Taishan forward fed his fellow Brazilian, the Al Ain goalkeeper redeemed himself with a solid stop.

Mohammed Awad Alla dragged his attempt across the face of the Al Rayyan goal at the end of a quick break soon after as Al Ain eventually settled while in the 24th minute Soufiane Rahimi had the ball in the net with a volley, but the effort was ruled out for offside.

The action swung from one end to the other, with Guedes denied on the goal-line by Khaled Al Hashemi’s clearance before Al Ain’s Matias Palacios shot from distance, only to see his goal-bound attempt shovelled away by Paulo Victor when he dropped to his right.

With a little over three minutes remaining in the half, Al Ain made the breakthrough. Rahimi was released down the left, the Moroccan edging towards the Al Rayyan goal before laying off for Romero to stroke his perfectly placed left-foot strike into the top corner.

Eisa had to be at his sharpest after the restart to keep out David Garcia’s attempt but there was little he could do in the 50th minute when Trezeguet converted Murad Haji Hussein’s cross from the right, the Egyptian controlling with his left before finishing with his right.

Palacios was inches away from restoring Al Ain’s lead in the 69th minute, rattling Victor’s crossbar from distance with the goalkeeper well beaten and the home side were to rue that miss six minutes later.

A quickly taken throw by Adam Bareiro into the penalty caught out the defence and, after allowing the ball to run across his body, Guedes smashed a low, left-foot shot into the bottom corner.

Victor gratefully clutched Rahimi’s 82nd minute header to his chest after the forward glanced Bandar Al Ahbabi’s free kick towards goal as Al Ain sought a lifeline in the dying minutes, but it was to prove an impossible mission with Al Rayyan holding on.