Richmond midfielder Kane Lambert is set to miss the next three rounds of the AFL season, with scans confirming he has a punctured lung and cracked rib.
Lambert was taken to hospital on Saturday night, having reported breathing difficulties after a painful collision in the Tigers' clash with Port Adelaide at the MCG.
The 24-year-old, playing his 19th game, was inadvertently crunched by Port Adelaide's Brad Ebert in a first-quarter marking contest.
The AFL club, reeling after a 1-5 start to the season, confirmed Lambert's diagnosis on Sunday morning.
"Kane Lambert has a cracked rib and punctured lung out of last night's game. Will be sidelined for 3-4 weeks," the Tigers posted on their Twitter account.
Lambert was one of Richmond's best in their only win of the season, a round-one victory over Carlton.
Captain Trent Cotchin will also miss the next two to three weeks after suffering a fractured cheekbone in the loss to Port Adelaide on Saturday night.
Cotchin didn't notify club medicos until after the match, when the injury occurred in the first quarter of the match.
The Richmond captain will have surgery this week and will miss crucial matches against Hawthorn and Sydney in the next two weeks.