Sir Alex Ferguson expects Michael Owen to be sidelined for up to five weeks and confirmed Owen Hargreaves is still a few weeks away from a first-team return.
Manchester United striker Owen had been in contention to start Tuesday's Carling Cup victory over Wolves after recovering from a recent groin complaint.
However, the 30-year-old picked up a hamstring injury in training and is now facing a few weeks on the sidelines.
Fellow England international Hargreaves, meanwhile, is still trying to build up his fitness following his long-term knee troubles.
Hargreaves has made just one fleeting substitute's appearance in the past two years and had appeared close to making his first-team return earlier this month.
The midfielder, though, is still receiving treatment and joins Owen, Ryan Giggs and Wayne Rooney in missing Saturday's Premier League game against Tottenham.
"Ryan should start training on Monday, I think he's progressed quite well now," said Ferguson.
"Michael Owen unfortunately picked up a hamstring injury in training. That's disappointing for him and he'll be out for four or five weeks.
"Wayne is still injured and resting, and Owen Hargreaves is still recovering from a long-term injury.
"I can't see [him playing in the next few weeks]. He was making very good progress when he first came back, but it seems to have stalled a little bit and he is back with the physios now.
"They're the only injuries we have at the moment and we have quite a strong squad at the moment. We hope it stays that way."
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