Xabi Alonso believes his Bayer Leverkusen side can still improve after they extended their unbeaten run to 48 matches across all competitions on Sunday, equalling Benfica's European record.

Champions Leverkusen thrashed Eintracht Frankfurt 5-1 in the Bundesliga to match Benfica's 48-game unbeaten run between 1963 and 1965 – a record across all competitions in Europe.

Alonso, however, still feels there is more to come.

"Our level, our consistency throughout the season is great. But we are always moving forward. We are always concentrating on the work and improving," he said.

Leverkusen, who are edging closer to an unbeaten season across all competitions, have two league matches remaining and are also set to face Kaiserslautern in the DFB-Pokal final on May 25.

They also hold a 2-0 lead over Roma at the halfway stage of their Europa League semi-final tie, with Thursday's second leg offering them the chance to surpass Benfica's record on home soil.

"It's a big challenge, we have two [Bundesliga] games left, it will be the perfect run. We will certainly try," Alonso said.

"We still have games to play to achieve our big goals in all competitions. The next game is important for us, the second leg of the Europa League semi-final: a chance to reach the final.

"In football it's sometimes difficult to stop. You have to prepare for the next game. The next game is a big game for us. Hopefully we have the chance to be in a European final again."

Leverkusen will play Bochum and Augsburg in their final two Bundesliga games. 

Should they progress to the Europa League final, they will then face either Atalanta or Marseille in Dublin on May 22, three days before the DFB-Pokal showpiece game.