Union Saint-Gilloise's Belgian defender Siebe Van Der Heyden (center) and Leverkusen's Iranian forward Sardar Azmoun (right) vie for the ball during the UEFA Europa League Group Quarter final First Leg football match between Bayer Leverkusen and Union St-Gilloise in Leverkusen, on April 13, 2023. (PHOTO / AFP)

LEVERKUSEN, Germany - Bayer Leverkusen's Florian Wirtz hit an 82nd-minute equalizer to rescue a 1-1 draw against visitors Union Saint-Gilloise of Belgium in their Europa League quarter-final first leg on Thursday.

The 19-year-old Wirtz, in top form since his return this year following a months-long injury break, fired in to cancel out Union's lead through Victor Boniface in the 51st and leave the tie open ahead of next week's return leg in Belgium.

The winner will face either Feyenoord or AS Roma in the semi-final.

The result snapped Leverkusen's six-game winning run across all competitions but Xabi Alonso's team are now unbeaten in their last 10 games.

Leverkusen were in control for much of the second half but missed a golden chance to level when Jeremie Frimpong's header from four meters out sailed wide of the post in the 78th

The hosts had their chances in an entertaining first half but it was Union, playing a sensational maiden Europa League campaign, who scored first.

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The Belgians launched a fine passing move six minutes after the restart and Boniface found space on the left to cut into the box and whip a shot past goalkeeper Lukas Hradecky for his sixth European goal in nine games this season.

The 22-year-old Nigerian, who joined the club last year from Norway's Bodo/Glimt, has taken the competition by storm and is currently joint top scorer of the competition along with Manchester United's Marcus Rashford.

Leverkusen were in control for much of the second half but missed a golden chance to level when Jeremie Frimpong's header from four meters out sailed wide of the post in the 78th.

Wirtz, fully recovered from last year's cruciate ligament tear, did it better five minutes later with a low shot into the bottom corner.

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"The second game decides this tie and we have shown what we are capable of," said Leverkusen keeper Hradecky. "Mentally it was very important not to lose tonight. We are in a position to beat any opponent."