England midfielder Owen Hargreaves is set to miss Manchester United's Champions League date at Roma on Wednesday due to a calf problem.
Hargreaves sustained the injury while warming up ahead of United's 4-1 Premier League win over bottom-of-the-table Derby County here at Old Trafford.
United are already through to the last 32 of European football's premier club competition and their position as group winners is secure regardless of the result in the Italian capital.
United manager Sir Alex Ferguson has already made it clear that a number of squad players will feature against Roma with Michael Carrick, who replaced Hargreaves on Saturday, set to start again while the former Bayern Munich midfielder receives treatment in Manchester.
"Owen strained his calf and we can't take chances at this time of the year. We had a look at it and we decided to bring Michael in for the Derby game," Ferguson said.
With Roma also through to the knockout phase, Ferguson has confirmed that reserve keeper Tomasz Kuszczak will start in Italy. There will also be rare opportunities for Jonny Evans, Gerard Pique, Chris Eagles and Dong Fangzhuo ahead of United's key league game against arch-rivals Liverpool next weekend.
Ferguson is generally pleased with his side's progress this season and added: "In some games we've played excellently and missed a lot of chances.
"Afterwards you're saying to yourself, 'I hope we don't regret missing these chances' but you have to be satisfied with your level of performance because that's what's important.
"I'll play a completely different team (against Roma). They were difficult conditions against Derby and it was a lot of exertion for the players involved.
"I'll take a lot of the first team squad with me because I need 18 players and some of the young players aren't registered.
The Scot added: "I'll go with a completely different team and Kuszczak will be in goal. We'll have Evans, Pique, Eagles, Carrick, (Darren) Fletcher, Anderson, (Louis) Saha, Dong and Nani. All of these players will play.
"It's a great opportunity for them. Roma have qualified and it's good for both teams and they will probably play one or two younger players themselves. I'm looking forward to it."
Derby manager Paul Jewell believes a major defensive improvement will be the key to his side kick-starting their season against Middlesbrough next week.
"The goals we're giving away are so elementary and they are basic errors so that's why we are where we are.
"We can't get different players until we get to January and we don't seem to be able to make the right decisions at the right time. Once we go a goal down, the belief just drains out of them.
"We've got to be positive against Middlesbrough next week. I'm still learning about the players and some of them haven't had a look-in yet. I'm still searching for my best team."