Mitch Marsh may be out for up to six weeks after the young West Australian all-rounder injured his left hamstring in the Warriors' 14-run loss to South Australia on Saturday.
Marsh had made 21 off 21 balls and looked to have placed his team in a winning position with Travis Birt (32), when he dived to make his ground after a second run.
The 21-year-old immediately clutched his hamstring on the ground and then thumped the turf in frustration before leaving the field a despondent figure.
After retiring hurt, Marsh did not return to bat when Western Australia lost their ninth wicket.
New West Australian coach Justin Langer confirmed the initial prognosis was a significant tear and a four to six week injury.
"We are going to get it scanned tomorrow, but the physio thinks he's torn his hamstring," Langer said.
"It's a huge blow for lots of reasons. We've got a Shield game and one-dayer in (Tasmania) next week, which he won't be available for.
"Then it's unlikely he'll be available for the Scorchers. He's pushing hard to play Australian one-day and Twenty20 cricket, so it's going to be hard if he's not playing."
The Marsh retirement appeared to significantly change a run chase that Western Australia had appeared in control of for the most part.
When Marsh retired hurt the Warriors needed 37 runs off 40 balls at 5-183 in response to South Australia's 9-219, but lost 4-18 thereafter to slump to defeat.
"It's like a wicket of one of your best players, so of course it hurt us," Langer said about its affect on their chase.
"But I thought we lost our way in the middle order. That's something we need to get better at next time."
Marsh had made an impressive start to the season in the shorter formats with scores of 24, 51 and 21 not out in the Ryobi Cup and 12, 52 not out, 5 not out and 20 for the Perth Scorchers in the Champions League.
He had only taken one wicket in Ryobi Cup matches this season, that of Tom Cooper in Saturday's loss to the Redbacks.
First Posted 18 November, 2012 11:09AM AEST
