Cristiano Ronaldo could be absent for Manchester United's Premier League clash with West Ham United on Saturday afternoon due to a neck problem.
The Portugal international returned from a hip injury to start Wednesday's contest at Brentford, helping his side record a 3-1 victory over the Bees in the Premier League.
Ronaldo was withdrawn in the 71st minute of the contest with Thomas Frank's side, although the substitution was only a precaution due to the Portuguese's recent hip issue.
Rangnick has said that the 36-year-old now has a problem with his neck and will need to be assessed before a final decision is made over his involvement against the Hammers this weekend.
"Cristiano is a question mark because he has a problem with his neck," Ralf told MUTV. "He received treatment yesterday for two-three hours and we will have to wait to see how he feels today."
Ronaldo has been in impressive scoring form for the Red Devils during the 2021-22 campaign, finding the back of the net on 14 occasions in 22 appearances in all competitions.
Man United are currently seventh in the Premier League table, two points behind fourth-placed West Ham ahead of Saturday's contest at Old Trafford.
