
Alonso made three changes to the side that started Sunday’s goalless Bundesliga draw at Wolfsburg, bringing in Jonathan Tah for Odilon Kossounou in defence, while Bakker and Florian Wirtz came in for Kerem Demirbay and Sardar Azmoun, who both dropped to the bench. The Werkself will now face Italian side Roma in the final four in May after they beat Feyenoord in extra-time.
An electric atmosphere inside Lotto Park – home of fellow Brussels-based club Anderlecht – saw Leverkusen get off to a lightning start. The game was barely two minutes old when Wirtz took advantage of a mistake at the back by the hosts to slip in Diaby, who rounded goalkeeper Anthony Moris to put Bayer 04 ahead on the night and in the tie.
Unperturbed by the setback, Union tried to move quickly through the middle, but the Werkself were quick to disrupt their play. Alonso’s men also still looked to attack and combine in front of the Belgians’ goal. A long ball up to Diaby in the 17th minute again caused danger as he raced down the right but put his shot into the side netting. Moments later, Bakker’s cross from the by-line to the far post was met by Frimpong, only for defender Koki Machida to get in the way.

Third time was the charm for Leverkusen as a turnover in the centre circle saw Diaby race away and lay the ball right to Hlozek. The Czech forward delivered a high ball towards the far post, where Bakker was perfectly positioned to put away first time for 2-0 on 38 minutes.
Both sets of supporters were vocal again after the restart. It was St. Gilloise who mustered up the first couple of efforts of the second half, but Lazare Amani’s long-range shot and Victor Boniface’s header amounted to nothing. By contrast, committed pressing from Bayer 04 paid off as Bakker hounded three Union players, including goalkeeper Moris. His clearance went straight to Frimpong, who just had to hit the target to put the visitors three to the good.
The Belgians hit back quickly with a goal of their own as a clearance landed with Terho, whose effort from outside the box deflected off Hlozek and past Lukas Hradecky to bring it back to 3-1 on the night. It seemed to awaken both Union and their supporters as the atmosphere grew more heated. Driven forward by that, the best chance fell to substitute Simon Adingra as he came in from the left and struck the frame of the goal.

However, it was Leverkusen who had the ball in the net next after they won the ball in their own half and Diaby fired off a shot. Moris was able to save but only parry for Hlozek to tuck home on 79 minutes and wrap things up.
Straight after the game, the Bayer 04 travelling party will return back to Leverkusen. They’re in action again on Sunday, 23 April (17:30 CEST) when they host DFB Cup holders RB Leipzig at the BayArena in the Bundesliga. After a run of midweek fixtures, the team now have a full week between games before going to Union Berlin on Saturday 29 April.
Match stats:
Saint-Gilloise: Moris – Nieuwkoop, Kandouss (Terho 46'), Burgess, Machida – Lynen, Teuma (Azzouzi 87'), Lapoussin – Vertessen (Adingra 31'), Amani (Puertas 81'), Boniface (Nilsson 81')
Bayer 04: Hradecky – Tapsoba (Kossounou 59'), Tah, Hincapie - Frimpong (Adli 71'), Amiri (Demirbay 59'), Andrich, Bakker - Diaby (Bellarabi 86'), Hlozek (Azmoun 86'), Wirtz
Yellow cards: Teuma
Goals: 0-1 Diaby (2'), 0-2 Bakker (38'), 0-3 Frimpong (61'), 1-3 Terho (65'), 1-4 Hlozek (79')
Referee: Antonio Mateu Lahoz (Spain)

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