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The newly-crowned Bundesliga champion and German Cup finalist took the lead through Wirtz before the half-hour mark when the midfielder scored with a simple low finish, capitalising on Roma's defensive error.

Andrich doubled the advantage in the 73rd minute, leaving Roma goalkeeper Mile Svilar with no chance when he fired an unstoppable shot from outside the box and under the bar.

The second leg will be played in Leverkusen next Thursday and the winner of the tie will face Olympique de Marseille or Atalanta in the final on May 22 at Dublin's Aviva Stadium.