Rashford has not found the net since scoring in United’s 3-0 win at Tottenham Hotspur back in October, during the final weeks of Ole Gunnar Solskjaer’s reign.
The 24-year-old’s season started late after undergoing surgery on a longstanding shoulder problem and, despite scoring three in his first four appearances following his return, he has since struggled for consistency in front of goal.
When asked for a reason behind Rashford’s form, Rangnick said: “Actually, I don't know. I think he's trying hard in training, he was doing well in training the last couple of days and that's why he was quite rightly in the starting XI.
“I think in the first half we found him quite often and in the first half he also tried to get into the box. In the second half, that was not that often the case, that's why I decided to make two changes, bringing on Anthony Elanga and Jesse Lingard.”
Rashford was replaced by Elanga in the 86th minute as United held on to reach the fourth round, having opened the scoring through Scott McTominay’s header early on.
After suffering defeat in their last Old Trafford outing against Wolverhampton Wanderers, Rangnick hopes that his players will use their victory over Villa as a springboard, Rashford included.
“Especially for strikers, it's important that they score goals on and off and have their moments of success,” he said. Of course it would be good if Marcus scored a goal but as long as he's trying, as long as he's playing well I don't see much of a problem.”
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