ROME - Goals by Florian Wirtz and Robert Andrich gave Bayer Leverkusen a 2-0 advantage over AS Roma in the first leg of their Europa League semi-final on Thursday as the German champions edged closer to their first European final in 22 years.

The newly-crowned Bundesliga winners and German Cup finalists, who recently overtook Juventus to claim the European record for the longest unbeaten streak across all competitions, lost 2-1 to Real Madrid in the 2002 Champions League final.

They won their only ever European title when they lifted the UEFA Cup in 1988.

"We fought well and showed a mature performance with a lot of discipline," coach Xabi Alonso told a press conference.

Bayer Leverkusen continued to dominate at Stadio Olimpico and Andrich made it 2-0 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

"We defended closely and compactly, so we are satisfied with the performance. But the return match has not yet been played."

While Leverkusen had an upper hand in the opening minutes, Roma grew into the game as the first half wore on and Romelu Lukaku could have given the hosts an early lead when he hit the bar with a header following a corner in the 21st minute.

However, the tables turned again in favor of Alonso's side who took the lead through Wirtz before the half-hour mark when the midfielder scored with a simple low finish, capitalizing on Roma's defensive error.

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Roma defender Rick Karsdorp miscalculated when he attempted to find Leonardo Spinazzola with a pass from the edge of their own box and Leverkusen's Alex Grimaldo took over the ball, cutting back to Wirtz who netted into the bottom right corner.

Leverkusen could have doubled the lead six minutes later but Jeremie Frimpong narrowly missed the target, striking from around the penalty spot with first touch.

But the visitors continued to dominate at Stadio Olimpico and Andrich made it 2-0 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.

Roma had a late chance in stoppage time through substitute Tammy Abraham, whose misplaced header from point-blank range sailed narrowly above the bar.

Both teams meet at the semi-final stage of the Europa League for the second season running, with the Italian side progressing to the last year's final thanks to a narrow 1-0 lead from their home first leg followed by a goalless draw in Germany.

Roma, who beat AC Milan 3-1 on aggregate in the quarter-finals, have reached the semi-final stage of a major European competition for the fourth consecutive season.

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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.