MITCH Robinson has been ruled out of Brisbane's semi-final against Greater Western Sydney on Saturday night.

The Lions' wingman came off during the final quarter of their 47-point loss to Richmond with a hamstring injury and scans on Monday confirmed the bad news.

A statement released by the club says it's a "hamstring tendon injury".

"The injury will be reassessed should the Lions proceed to the preliminary final," the statement said. 

Robinson has been critical to Brisbane's dramatic rise up the ladder in 2019, playing all 23 games, averaging 22 disposals and kicking 17 goals.

A number of players from the club's unbeaten NEAFL team are in contention to replace the hard-nut, including Lewy Taylor, Rhys Mathieson, Cedric Cox and Ryan Bastinac.