The sides meet at the Stade de France this weekend with 25 points separating them in Ligue 1 and with PSG having already beaten Lyon 4-0 this season.
However, leaders PSG go into the game off the back of a painful UEFA Champions League exit to Chelsea and a 1-0 defeat at Lyon last Saturday.
Umtiti feels Lyon can add to PSG's woes this weekend - although he is well aware that Laurent Blanc's side will be intent on revenge.
"This game is going to be different (to the 1-0 win in Lyon). Paris have had back-to-back defeats. They are really going to do everything to win this trophy," he told the official Ligue 1 website.
"When you hear them talking, they really want to win it, just as we do of course. It's going to be a game filled with even more commitment.
"It's going to be decided on the smallest details and we have to be on our mettle tactically."
PSG's woes have come at a time when Zlatan Ibrahimovic has been out injured with a hamstring problem.
The talismanic Swede has scored 40 goals in all competitions this term, but, even without him, Umtiti feels PSG are still favourites for the cup.
"On paper, Paris should win two or three-nil, but you never know how the match will pan out," he continued.
"If everyone does their job, we can cause them problems. But it's true that we're not favourites."
