Manchester United says defenders Rio Ferdinand and Rafael da Silva face lengthy layoffs after they both picked up injuries.

The club said right back Rafael will miss the first 10 weeks of the season after injuring a shoulder in training ahead of Sunday's opener against West Bromwich Albion.

And during United's 2-1 victory, Ferdinand sustained a hamstring injury that manager Alex Ferguson says will rule the England center back out for six weeks.

Ferguson also says United could be without another center back, Nemanja Vidic, for two weeks after he came off with a calf injury.