Striker Romelu Lukaku and defender Diogo Dalot both missed training on Tuesday ahead of Manchester United's crunch Champions League match against Juventus, but captain Antonio Valencia and Marouane Fellaini returned.
The game in Turin on Wednesday pits Juve superstar Cristiano Ronaldo against the team he played for from 2003-09.
Lukaku has been out of form, having failed to score for his club since mid-September, and was dropped to the bench for United's 2-1 home victory against Everton.
The Belgian, who has scored only four Premier League goals so far this season, missed the win over Bournemouth last Saturday due to an injury picked up in training the day before.
Right-back Dalot, Fellaini and Valencia have all been absent due to injury but the latter two were part of the main group in Jose Mourinho's training session at Carrington before the travelling squad flew to Turin.
Serie A leaders Juventus are top of Group H on nine points, with United second on four. The Italians won the clash at Old Trafford 1-0 last month.