These were completely different circumstances than the sides’ dismal 0-0 league draw a couple of weeks back, and a renewed urgency saw Bayern lead the tie inside nine minutes.
Michael Olise’s cross from the right was spotted by Harry Kane, who darted in front of Nordi Mukiele to fire in his first goal in five matches – ending his longest drought for Bayern.
A complacent Dayot Upamecano then nearly undid the hosts’ hard work by giving it away to Jeremie Frimpong, though the makeshift centre forward failed to beat Manuel Neuer one-on-one.
But that chance began to look like a flash in the pan for Leverkusen, who subsequently endured an onslaught from Bayern. Jamal Musiala somehow headed onto the bar from point-blank range from a corner, before long-range efforts from Kingsley Coman and Joshua Kimmich had Matěj Kovář scrambling despite sailing wide of the mark.
Alonso will have felt fortunate to see his side make it to the break without a worsening of the situation, especially with tempers flaring just before HT.
However, the visitors’ luck ran out less than 10 minutes after the restart. Kimmich’s ball looked to be floating into the gloves of Kovář, but the Leverkusen stopper completely misjudged it and ended up dropping it at the feet of Musiala for an easy tap-in.
Mukiele further compounded his side’s misery by earning himself a second yellow card for stepping on Coman’s heel, before Edmond Tapsoba gave away a penalty for hauling Kane to the ground.
The England international picked himself up and fired into the top right from the spot, netting for the 17th time in the UCL since relocating to Bavaria – more than any other player in that time frame.
There was little that Leverkusen could do other than sit back in the final stages to keep the deficit at three, leaving them a huge task next week.
The second leg will no doubt be a different story, but Bayern have a strong aggregate lead and hold a 10-match unbeaten streak.
It was clear that many of Leverkusen’s problems tonight came from some poor personnel selections, but that’s something they can fix for a second leg in which they will need to at least replicate their 3-0 win H2H win at the BayArena just 12 months ago.
Flashscore Man of the Match: Harry Kane (Bayern Munich)
