I say start Lenglet and if, and only if, we are comfortably ahead in the tie and in control of the match, give him an 80th min cameo sub. That way, you see how fit he actually is and he gets his wish of playing against his former club. I totally get why he wants to play this game, with family/friends who can’t travel to Barcelona all the time now being able to watch you play. He deserves that and the warm reception he’ll get from the Lyon fans but we shouldn’t let that jeopardize our most important objective this season.
It’s just too much of a risk to start him without him having at least a couple matches under his belt in a game of this magnitude. You can’t fuck around with knees and rush returns and there is a particular psychological aspect to knee injuries that a lot of people overlook and I’m afraid Sam might be doing that atm, given the context surrounding this match. For his career’s sake, we have to carefully reincorporate him into the starting 11 and rotate him carefully. With Verm gone, we cannot afford any more losses and a reoccurrence of an injury would spell trouble for Sam.
Great to see him back though and hope he is mainly fit for the Siege of Madrid.