Rooney had not suggested there was any problem when he tweeted this morning that he was heading for training after dropping son Kai off at his nursery.

However, he was missing as United went through their paces at their Carrington training complex.

Sir Alex Ferguson confirmed Rooney is a doubt for Manchester United's Champions League semi-final second leg with Schalke at Old Trafford tomorrow. 

Ferguson reported Rooney has "a tight hamstring" and the forward will be monitored before the United boss finalises his line-up.

Darren Fletcher will play some part after recovering from the virus that has kept him out for a month, although, with his side two goals up from the first-leg, Ferguson will have Sunday's Premier League showdown with Chelsea in his mind when he makes his selection.

With a crucial Premier League encounter with Chelsea to come on Sunday Ferguson will be giving plenty of thought to the players he intends to choose.

Fletcher, out for two months with a virus, was training and is available but Brazilian defender Fabio, who suffered a knock in Sunday's defeat at Arsenal, did not train and seems unlikely to be involved.

Denmark keeper Anders Lindegaard has recovered from the knee ligaments injury that has ruled him out for a couple of months should Ferguson wish to rest first choice keeper Edwin van der Sar.

Team (from): Van der Sar, Kuszczak, Lindegaard, Rafael, O'Shea, Ferdinand, Vidic, Smalling, Evans, Brown, Evra, Valencia, Scholes, Anderson, Carrick, Fletcher, Gibson, Park, Giggs, Nani, Obertan, Rooney, Berbatov, Owen, Hernandez.