Thomas Tuchel on Monday urged his Champions League-winning Chelsea team not to underestimate Lille during the two matches of their last-16 tie.
Under Christophe Galtier Lille pipped Paris Saint-Germain to the 2021 Ligue 1 title.
He left for Nice and other key players departed as Jocelyn Gourvennec took over as head coach.
However, the team has struggled under the new regime and lie 11th - 23 points behind pacesetters Paris Saint-Germain and nine points off third spot - the final berth allowing access to next season's Champions League.
Drawing on his experience as coach of PSG, Tuchel said Lille would turn out at Stamford Bridge on Tuesday night free of pressure.
Pressure
"They have the chance to play this game as underdogs with nothing to lose and they will take it from there," added the German.
"We all know how physical French football is. Players are very brave in one-on-one challenges and very disciplined on the ball."
During his two years as PSG boss, Tuchel steered the side to six trophies including two French titles. They also reached the final of the Champions League in August 2020 where they went down 1-0 to Bayern Munich.
Tuchel was sacked in December 2020 and was within weeks drafted in by Chelsea who had disposed of Frank Lampard.
Success
In May, Tuchel led the west Londoners to their second success in European club football's most prestigious tournament. He followed it up with the Uefa Super Cup and the Fifa Club World Cup.
Speaking about Lille under Galtier, Tuchel said: "They had a fantastic coach and group of players and you felt they could fight for a chance in the Champions League. Last season they became French champions, which is huge.
"Losing Galtier and couple of players is a huge change. If the change is so big it can take time for things to settle."
Chelsea's quest for next season's Champions League fares better than Lille's. Chelsea edged past fellow Londoners Crystal Palace 1-0 on Saturday afternoon to maintain their hold on third place in the Premier League.
After the game against Lille, Chelsea face Liverpool on Sunday in the League Cup final.
"It is the moment to be super focused and not worry about the big picture," added Tuchel.
"Because if we do that it will make us look at a lot of different pictures and environments. The Premier League isn't about knockout matches, it's about consistency.
"We will bring the best group for the game against Lille and then we will take care of Sunday's match."
