ROTHERHAM United are monitoring the fitness of new boy Matt Olosunde after the young right-back was forced to miss his first match of the season.
The American defender has been a revelation for the Millers in his debut campaign in senior football following a two-and-a-half-year spell in Manchester United's youth ranks.
But a hamstring issue ruled him out of last Saturday's 0-0 home draw with Shrewsbury Town, leaving the Millers sweating on his availability for next weekend's League One trip to Bristol Rovers.
"His hammys are tight and we'll see how he is," manager Paul Warne said. "He might have a scan.
"To be fair, in every game he's played his hammys have been a bit tight. I suppose it was inevitable he would break sooner or later.
"He's only 21 and it's his first season as a pro. I'm hopeful he'll be fit."
Olosunde dropped out on the eve of the Shrews stalemate, which moved Rotherham up to 13th in the table, allowing experienced Billy Jones, aged 32, to return from a foot injury.
"Matt trained on Friday but dropped out and said he was too sore," Warne said. "That was disappointing, but I thought Billy did really well considering it was his first game this season.
"He's got good muscle memory. He's played that many games in his career he knows what's doing."
Rotherham were frustrated by Shrewsbury's massed defence and time-wasting and Warne rued the injury absence of two of his fastest players, striker Kyle Vassell and winger Chiedozie Ogbene, who also have hamstring problems.
"It was a day when a Chieo or a Vass might have created something out of nothing," the boss said. "We just didn't answer enough questions."
With Rotherham chasing the win late on, the Millers brought off winger Jake Hastie and replaced him with midfielder Shaun MacDonald, leaving wide man Julien Lamy on the bench.
Lamy, 19, is untried has yet to make his debut after a leg injury. Rotherham would rather he built up his conditioning in reserve games before they seriously consider him for first-team action.
Glasgow Rangers loanee Hastie, 20, had scored in all of his first three outings and Warne said: "He didn't look as sharp against Shrewsbury. That's not a criticism. He's not up to full match-fitness yet. He's a young lad in his first season in England.
"He'd been instrumental for us in his previous three games and because of that we probably noticed his lack of effect even more."
The manager welcomed a free week to prepare for the trip to the Memorial Stadium where former Rotherham striker Jonson Clarke-Harris lies in wait.
"We haven't got a midweek game this week so we can get them nice and fresh for the journey to Bristol," he said.