Melbourne Storm winger Marika Koroibete is fighting a race against time to be fit for his club's do-or-die home preliminary final against North Queensland.
The 22-year-old has had stitching and plastic surgery around his achilles after suffering a laceration in Melbourne's qualifying final win over the Roosters.
Storm football manager Frank Ponissi said the club was initially concerned after Koroibete made little to no progress in the immediate days after the injury.
"There's optimism in last 48 hours that he's moving a lot better. He's walking without a limp now," Ponissi said.
The Storm's leading tryscorer this season will need to complete a full training session on Friday to secure a spot in what would be his first preliminary final appearance.
"The big test will come on Wednesday when he'll have his first run," Ponissi said.
"He won't do a full session but he'll do some running. If he can pull up from that OK, if he can train again fully on Friday, then he'll be right.
Ponissi said if there is any threat the stitching around Koroibete's achilles could split, he will not play against the Cowboys.
"He's lost a lot of strength in his calf in the last 10 days so he's got to build up that strength really quickly - that's probably the thing holding him back the most," Ponissi said.
"If he can make the same progress in the next 48 hours that he has in the last 48 then he'll be a better chance of playing than not playing.
Storm prop Jordan McLean is recovering from a knee injury, but is likely to play in Saturday night's clash at AAMI Park.