Flowers left the game early on Sunday during the Ravens' game against the Cleveland Browns after linebacker Mohamoud Diabate collided with his knee during a tackle.
"It's not a season-ending injury. It's going to be day-to-day and him doing everything he can do to get back as soon as he can," said Harbaugh.
Flowers ended the regular season in an unfortunate way, especially after being named to the starting Pro Bowl roster following a season in which he put a 1,059 yards (career high) and four touchdowns on 74 receptions.
Flowers was the 22nd overall pick in the 2023 NFL Draft and has become an established number-one wide receiver for the Ravens. He is also the first wide receiver in Ravens franchise history to be elected to the Pro Bowl.
Without Flowers, the Ravens are going to rely heavily on wide receiver Rashod Bateman and tight ends Mark Andrews and Isaiah Likely to pick up the load if he's unable to go on Saturday night.
In both games against the Steelers this season, Flowers put up 139 yards and one touchdown on just seven receptions.
The stud receiver also posted to social media that he cut off his dreads in time for the playoffs.