Sir Alex Ferguson will give Nemanja Vidic and Rio Ferdinand every opportunity to prove their fitness ahead of Manchester United's Champions League clash with AC Milan after the injured pair joined their team-mates on the flight to Italy.
United hold a 3-2 first-leg semi-final advantage ahead of Wednesday's return clash and Ferguson will leave a decision on the fitness of Ferdinand and Vidic until after training on Tuesday evening.
Ferdinand has not played since aggravating a groin injury in a Premiership clash against Middlesbrough ten days ago, while Vidic has been sidelined since breaking his collarbone against Blackburn Rovers on March 31.
"It is too early to say whether they will play," admitted Ferguson.
"They will travel and we will assess the situation after training."
The Red Devils named a makeshift defence in last week's first leg with Wes Brown partnering Gabriel Heinze in the heart of the defence.
With Patrice Evra suspended, it seems likely that either Ferdinand or Vidic will play with Heinze reverting to a more regular left-back berth.
Elsewhere, Louis Saha could be named on the substitute's bench after finally shaking off the hamstring injury that has dogged the French striker since the beginning of April.