Goals by Florian Wirtz and Robert Andrich gave the newly-crowned Bundesliga champions a two-goal advantage over last season's runners-up Roma, extending their unbeaten run to 47 matches in all competitions.

"We made good transitions once they were open and we had enough spaces, the commitment and the discipline from the players have been fantastic," Alonso said. "But there is still a game to play.

"We have used that system before, especially because we have players who can play in different roles ... Today the game plan was quite clear, and we really performed at a very high level.

"We could have scored more. But to be fair, they could have scored as well. The result could have been a little bit different, but it's fair enough. It was not difficult to motivate the players."

Leverkusen won their first meeting with Roma in almost 20 years, since they beat Italy's capital side 3-1 at home in October 2004 in the Champions League group stage. They were winless in five games against Roma since.

"It was a serious and careful match, we were smart and mature. They had their chances, the lead gave us more confidence to do our things in possession and non-possession," Alonso added.

"Up front, we have fast players. In the second half, we did not concede anything - we knew if we were careful and solid, we would then have our chances. The team found the right compromise.

"2-0 is a good result, we go home happy but cautious. What we are doing in this season is outstanding. We have quality players with a very high level of focus, the most difficult thing is to be consistent.

"We don't want to stop - we want to go on like this until the end of the season."

Leverkusen scored yet another last-gasp equaliser to get a 2-2 draw against VfB Stuttgart on Saturday that allowed them to maintain their record unbeaten run intact.