If Chelsea's performance continues to decline and of course it will be a pressure on the team, at least the problem will have an impact on their performance as well. But if some key Chelsea players can get back into shape and keep them safe until the match against Lille, then of course Chelsea have a great chance of qualifying. I'm just worried that the pressure on the team can't be overcome, because after all even though Lille looks worse in the domestic league but the fact that throughout the group stage Lille can prove their capacity and Lille still can't be underestimated.
Even if Chelsea continues to slip, and Lille improves its game, then 99.99% you can be sure that Chelsea will still be the winner of this pair. Lille is very bad this season - 11th in the weakest of the top leagues. Making it to the playoffs from the Champions League group stage is easy to explain - they had the weakest group (possibly one of the weakest in history) and scored only 11 points. I think Chelsea will never get nervous about this confrontation and will easily succeed here.