Two goals against the run of play stunned the favourites, who later had two goals ruled out, and the European champions await in the last four
Al Sadd booked a dream Club World Cup semi-final date with Barcelona after overcoming African representatives Esperance 2-1 in the quarter-finals at Toyota Stadium.
Two late goals for the Tunisian side were also controversially ruled out for offside, leaving the 1,000 or so of travelling supporters infuriated, pelting the Al Sadd players with bottles during the closing stages of the match.
Esperance will feel hard done by, having had more shots on goal, but many were woefully wasted. The Qatari side converted from their first real effort against the run of play after being pinned back for most of the first half.
Abdoul Kader Keita's shot from a tight angle, following a quickly taken free kick on the halfway line, was only parried to the far post by Moez Ben Cherifia. Khalfan Al Khalfan then reacted the fastest to nod home on the goal-line to hand his side an unlikely lead.
Esperance had nearly broken the deadlock on 19 minutes when Yannick Ndjeng's shot came back off the inside of the upright with Mohamed Saqr beaten. Youssef Msakni was then also guilty of wasting opportunities, despite looking lively early in the game and with the Asian side's defence appearing unconvincing.
Al Sadd's clinical efficiency would prove to be key to their success, however, as they doubled the lead minutes after the restart with their second effort on goal. Nadir Belhadj's free-kick to the far post was headed back across the goalmouth by Lee Jung Soo, and poked in on the line by the unmarked Abdulla Koni.
Esperance did manage to pull a goal back as Ousama Darragi's innocuous looking free-kick glanced off several heads before nestling in the far bottom corner. Several more opportunities were passed on, however, handing victory to the Asians.
Al Sadd's reward for the victory is a meeting with European champions and tournament favourites Barcelona on Thursday.