RICHMOND will be without Mykelti Lefau for the remainder of the season following confirmation he has ruptured the anterior cruciate ligament in his right knee.

The promising key forward left the ground during the final quarter of the Tigers' 30-point loss to Geelong on Saturday night after landing awkwardly in a marking contest.

Scans on Sunday morning confirmed the Tigers' worst fears, with Lefau now the fifth player on their list with an ACL rupture - Judson Clarke, Josh Gibcus, Sam Naismith and Tylar Young are sidelined with the same injury.

Lefau has previously ruptured the ACL in his left leg while playing in the VFL in 2022.

Richmond footy performance manager Tim Livingstone said it was shattering news for the talented 25-year-old.

"Football can be a cruel game sometimes, and for Mykelti, who has been in terrific form, this is an unfortunate way for his debut season to finish," he said.

"Mykelti has not put a foot wrong since he joined our AFL program in the pre-season, and we know he will attack his rehab with the same professionalism and energy that has held him in such strong stead this season.

"We will give him our support every step of the way and help him to return to action and to continue with his promising career in 2025."

Lefau has kicked 14 goals from 10 matches since making his debut in round three against Port Adelaide.

The New Zealand-born forward was again a strong contributor for the Tigers on Saturday night, booting multiple goals for the fifth time this season.