I am impressed of the amount of people who wants Laporte to start. The same guy that has made several huge mistakes in vital moments at UCL. Two gifted goals against Tottenham, Lyon and Madrid (I still can't believe how he chose to not even try to close Vinicius in his goal, and his penalty...). Walker has never made mistakes in vital UCL games, actually quite the opposite. He loves defending, while Laporte is great when he is under less pressure which these games are not. We will need to defend sometimes and be aggressive, and Akanji and Walker are way more comfortable on that.