Lyon defied expectations to beat Juventus in the Champions League round-of-16 first leg on Wednesday, emerging 1-0 winners thanks to a first-half Lucas Tousart goal.
The hosts then took the lead on the half-hour mark while a bloodied Matthijs de Ligt was being treated off-pitch for a cut to the head -- caused by an accidental stamp from teammate Alex Sandro. Houssem Aouar surged in from the sideline to provide a cross for Tousart, who sent a cushioned volley past Szczesny.
Juventus grew into the game in the second half, but were unable to muster a single shot on target from 14 efforts, let alone find what would have been an important away goal ahead of the second leg in Turin on March 17.
The closest the visitors came to equalising was when Paulo Dybala found the net with three minutes remaining in the second half, only for the goal to be disallowed as a result of the Argentina forward straying offside.
In the closing moments, Cristiano Ronaldo and Dybala both hit the turf in the Lyon box, but referee Jesus Gil Manzano was unimpressed by their calls for penalties.
"It was an almost perfect performance," Lyon sporting director Juninho told RMC Sport after the match. "Winning 1-0 against Juventus, nobody thought we could.
"Of course, we are very happy, but we cannot forget that this is just the first leg."
Juninho also praised Lyon midfielder Bruno Guimaraes, saying: "Bruno is a player who has been thoroughly educated. That is rare in Brazil, but we came across a team that trains its players well.
"He is a player with great humility, who always wants to learn. We see that he has the ability to see situations before they arise.
"He really is a very, very good player. He has all the qualities to become a great, great player. Today, national team members were here. I think he will be called for Brazil's first team soon."
Meanwhile, Juventus captain Leonardo Bonucci said: "We messed up our first half, sometimes it happens.
"We gifted one half and they scored at a moment when they were good at hurting us."
The Serie A leaders are next in action on Sunday, with their clash against third-placed Inter Milan being played behind closed doors following a coronavirus outbreak in northern Italy.