The Scottish giants went to the locker room two up, thanks to goals from Massimo Donati and Scott McDonald.

Three second-half goals from Shaun Maloney, McDonald and Chris Killen ensured Ahli had a night to forget at the 90,000-seat Wembley Stadium.

The Red Devils will face European and Spanish champions Barcelona on Sunday in their final game of the tournament while Celtic will meet England's Tottenham Hotspur.

Same Formation

Ahli coach Hossam Al-Badri played with the same 4-4-2 formation he deployed in Tuesday's 2-0 defeat to Harras Hodoud in the Egyptian Super Cup.

Egypt defender Wael Gomaa returned to the starting line-up to replace skipper Ahmed Al-Sayed, who was sent off against Hodoud, and partner Mohamed Samir in the heart of Ahli's defense.

Liberian striker Francis Doe played as a lone striker to make his debut.

Celtic had the upper hand during the first half and were unlucky not to break the deadlock more than once.

McDonald wasted two early chances to put the British side in front.

He had a close-range shot superbly blocked by Ahli keeper Amir Abdul-Hamid before heading astonishingly over the bar with the goal gaping.

Ahli's only goalscoring opportunity fell to Doe after 12 minutes when he latched onto a deft pass from Mohamed Abou-Treika to go one-on-one with Artur Boruc, who blocked the Liberian's low shot.

Maloney and Marc-Antoine Fortune were unlucky to see two successive efforts strike the post but Donati made amends on 31 minutes.

Ahli's right-back Ahmed Ali was robbed on the edge of the area to allow Donati to collect the ball, evade a poor challenge from Samir and round keeper Amir Abdul-Hamid to slot into an empty net.

Dreadful Errors

More dreadful errors from Ahli defenders helped Celtic increase the gap.

A defense-splitting pass six minutes before the break released McDonald, who was brought down by Abdul-Hamid as the referee immediately pointed to the spot.

The Australian striker stepped up to send Abdul-Hamid the wrong way and double Celtic's lead.

Maloney added a controversial third goal on 49 minutes with a low shot from inside the area that found its way past the motionless guardian. Television replays showed that he was in an offside position.

McDonald scored his second of the night ten minutes later to widen Ahli's misery. He curled a sublime right-footed shot into the far top corner amid no resistance from opposing defenders.

Killen completed the rout with seven minutes remaining when he converted a mis-hit shot from close range.