Sundowns Thapelo Morena (L) vies for the ball with Luanda s Augusto Carneiro (R) during the CAF Champions League second leg semi-final football match at the FNB Stadium in Johannesburg on April 23, 2022 (AFP)
Although Sundowns lost 2-1 away in the quarter-final first-leg, they were expected to overturn the deficit at the Soccer City Stadium, south of Johannesburg.
They wasted a plethora of chances in a goalless first half, with in-form striker Peter Shalulile firing over the bar with the goal at his mercy early on and Themba Zwane missing a penalty on the stroke of halftime after hitting the post.
They finally made their dominance count in the 49th minute when Petro keeper Wellington pushed a tame, angled free kick into the path of Brian Mandela, who made no mistake on the rebound.
The goal gave Sundowns an advantage on the away-goal rule but Petro netted against the run of play after being awarded a penalty for a reckless challenge by defender Andile Jali, with Brazilian forward Tiago Azulao tucking away the spot-kick in the 64th minute.
Petro held on for a memorable victory over their fancied opponents, 3-2 on aggregate, to reach the Champions League semi-final for only the second time and the first since 2001.
Sundowns, winners of Africa's premier club competition in 2016, became the second high-profile last-eight casualty after Tunisia's Esperance, the four-time champions who lost 1-0 on aggregate to Algerian side ES Setif on Friday.
Petro will face either Morocco's Wydad or Algeria's Belouizdad in the semis, with reigning champions Ahly of Egypt taking on Setif in the other last-four clash.
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