Wirtz's deft chip set up Moussa Diaby's late winner in Thursday's 3-2 victory over Celtic to put Leverkusen in the Europa League's last 16.

Wirtz's ascendancy has been nothing short of meteoric since Leverkusen signed him from the Cologne Under-17 team in January 2020.

His seven goals and nine assists in 16 games for Leverkusen this season speaks volumes.

"I have learnt so much - the (senior) game is so different to youth football," the teenage attacking midfielder told AFP.

"Against big clubs like Celtic, you have to prove yourself on a different level.

"When you manage to make a comeback like that," he added as Leverkusen scored two late goals against the Scottish giants, "it gives you some momentum which we want to carry into the Leipzig game on Sunday."

Leverkusen, who are fourth in the Bundesliga and on course for the Champions League next season, have a history of losing talent to bigger clubs.

Michael Ballack was 25 when he left on a free transfer for Bayern Munich in 2002, then went onto captain Germany and star for Chelsea.

Kai Havertz, still only 22, joined the Blues for 80 million euros ($90 million) in September 2020, then scored the winning goal for Chelsea in last season's Champions League final.

Having seen Havertz's shine in the Premier League, Wirtz knows he is already on the path to similar success.

"Every small boy dreams of playing for a really big club, I don't know what will happen in the next few years, I only know that my head is fully focused on Leverkusen," he said.