The injury-hit Melbourne Rebels will be sweating on a batch of fitness tests later this week as coach Tony McGahan faces the prospect of fielding a severely under-strength team in Christchurch.

As if the prospect of heading to New Zealand to face the Crusaders wasn't daunting enough, captain Nic Stirzaker (ankle), fullback Mike Harris (ankle) and locks Lopeti Timani and Luke Jones (both concussion) will face tests before their availability is known.

But in somewhat better news for the now-out-of-contention Rebels, wingers Jonah Placid (nose) and Sefa Naivalu (leg) have been declared fit to play despite coming off early in the weekend's home loss to the Stormers.