Les Gones had won just one of their last nine matches in all competitions and drew at Real Betis in their Group I opener, while Vitoria opened their campaign with a 4-0 win over the group's weakest side, HNK Rijeka.
Despite the home side's dominance, the two sides were forced to settle for a score draw.
Read how the match unfolded in our live commentary.
5.37pmThis is a big game in the group. On one side, Lyon are in a poor run of form, but drew what is arguably their hardest match of Group I by taking a point in Spain against Real Betis.
5.39pmOn the other hand, Vitoria smashed HNK Rijeka in their first match of Group I, but they are arguably the weakest outfit in the table. However, the Portuguese cup holders sit 10th in their domestic league, nine points behind leaders Porto, but they are largely expected to finish around there.
5.41pmLyon have won just one of their last nine games in all competitions, including both legs of their Champions League qualifier against Real Sociedad. Remi Garde will be hoping that his thin squad can kick-start their season here tonight.
5.42pmRight, let's bring you some team news, starting with the hosts.
5.46pmRemi Garde makes five changes to his side following their 0-0 draw with Lille in Ligue 1 at the weekend.
5.48pmHenri Bedimo, Mehdi Zeffane, Nabil Fekir, Clement Grenier and Jimmy Briand all drop out of the team, with Jordan Ferri, Steed Malbranque, Alassane Plea, Gueida Fofana and Alexandre Lacazette all coming into the starting lineup.
1 minKICK OFF! Lyon get us underway and are playing from right to left in this first half.
2 minInterestingly, Lyon are wearing their navy away strip, while Vitoria are wearing an all-white strip.
6 minIt's been a scrappy start to the match with a lot of fouls going in.
9 minLyon have a free kick in a good position just left of centre outside the box. A cross should be coming in from this, but instead the ball is rolled for Fofana to have a smash at goal. However, it's so obvious, and Vitoria can close down and clear.
14 minGomis races down the right and floats a cross towards an unmarked Lacazette at the far post from the edge of the box. However, the defender senses the danger and opts to nod it behind.
17 minIt's been a decent start to the match. Lyon have largely been in control and have had more chances and possession, but Vitoria look nifty on the break. This is going to be an interesting battle.
20 minCHANCE! The first real effort of the match falls to Lyon and Lacazette in particular. He dribbles in from the left and shoots from the edge of the box in among a crowd of bodies. However, his low shot bounces just wide of the near post.
22 minLyon have scored just five goals in their last nine games, so they desperately need to find a spark in front of goal.
23 minCLOSE! Vitoria go fractions away from taking the lead through Chris Malonga. The ball bounces inside from the right touchline, and Malonga hammers a dipping half-volley towards the top corner. Lopes in the Lyon goal looks beaten, but it flashes just wide.
26 minThere's a break in play as Gomis receives some medical attention after landing heavily when challenging for the ball in the air.
27 minCLOSE! The flag was up anyway so this wouldn't have counted. A free kick from the right is lofted into the box where Gomis heads the ball just wide. However, he was offside anyway.
29 minVitoria go close after curling a shot towards the far corner from the left, but it's just over the bar.
33 minVery nearly a chance for Lyon as the cross comes in across the face of goal from the left. It heads between the goalkeeper and defenders, by Gomis is just unable to reach it with his diving header.
34 minSamuel Umtiti is down at the moment and looks in some pain. It looks as if he may have pulled a muscle when he made a pass. I'm certain he'll come off here.
35 minLYON CHANGE Umtiti cannot continue and Medhi Zeffane, who only made his debut on Saturday, is on.
35 minCLOSE! Very nearly an opener for Vitoria from the corner. Ba races from the back of the box to lose his marker and gets to the ball first, but he can only head over from the penalty spot.
39 minGOAL! Lyon 0-1 Vitoria de Guimaraes (Moussa Maazou)
39 minVitoria take the lead and this comes from a long punt downfield. Maazou gets to the ball first, holds off the defenders, before slamming a low shot into the bottom corner from just inside the box.
40 minYELLOW CARD Maazou is booked for going over and celebrating with his fans.
44 minThe Vitoria fans are in fine voice behind Lyon's goal. It's been 59 years since a Portuguese team was victorious here.
6.47pmWell, well, well this is a bit of a surprise. Despite Lyon being in control of the half for large periods, it's Vitoria who lead.
6.48pmThey have had a few chances, but Vitoria are in front due to Maazou's goal just before the break. Lyon have had a couple of opportunities, but haven't managed to test Douglas in the visitors goal.
7pmThe teams are back out at the Stade de Gerland.
46 minKICK OFF! Vitoria, playing from right to left, get the match back underway.
47 minCLOSE! Vitoria have a corner from the right which is poorly cleared by Lyon. It falls to Andre Santos on the edge of the box, who side-foots it towards the top corner, but it takes a slight deflection and flies over.
50 minCHANCE! Lyon have a corner from the right which Vitoria can only flick to Steed Malbranque at the far post. He hits a dipping shot first time, but it's straight at Douglas.
53 minYELLOW CARD Pedro Correia goes into the book for wrestling Lacazette to the ground.
53 minGOAL! Lyon 1-1 Vitoria de Guimaraes (Maxime Gonalons)
53 minThe hosts are level through the captain. Mvemba curls a free kick outside the box in towards the near post, and Gonalons helps it into the corner with his head. Game on.
56 minThat goal has really lifted the home fans, which is exactly what Lyon needed.
60 minYELLOW CARD Leonel Olimpio goes into the book for a strong challenge on Jordan Ferri.
63 minLYON CHANGE Steed Malbranque is replaced by a man 11 years younger than him - Clement Grenier.
65 minLyon have been on top since they found that equaliser, but haven't been able to create any more chances since then.
65 minCLOSE! I thought this had gone in, but Lyon are fractions from going in front. Grenier whips in a superb cross to the far post which lands on the head of Fofana, but he nods it just wide. Should have scored.
66 minVITORIA CHANGE Chris Malonga is off, and Plagne comes on.
70 minThis game is so finely poised now. Lyon, with the fans behind them, have edged it since they drew level, but you just wouldn't rule out this Vitoria side on the break.
75 minVITORIA CHANGE Brace yourself for this: Andre Andre is coming on in place of Andre Santos.
78 minGrenier curls a free kick from the left just outside the box with his right foot towards the near bottom corner. His effort looked to be going just wide, but Douglas opts to make the save anyway.
80 minDespite their good play in the first half, I imagine that Vitoria would be happy to take a point from this match now.
83 minLYON CHANGE Gael Danic is on in place of Mvemba.
85 minInteresting scenes here as Ba makes a brilliant challenge just inside the box on Lacazette, but the referee awards a penalty. After furious outrages from the Vitoria players, the referee talks to his fellow officials and awards a corner.
89 minVITORIA CHANGE Tiago Rodrigues makes way for Moreno
90 minYELLOW CARD Kone is given a yellow for a late challenge.