Striker Romelu Lukaku has been ruled out of Manchester United's Champions League match at Juventus due to a muscle injury and is also a doubt for Sunday's Premier League derby with Manchester City, manager Jose Mourinho said.

Lukaku, who has four goals for United this season and has failed to score for his club since mid-September, missed last Saturday's trip to Bournemouth with a muscle injury.

"(Lukaku is) injured for tomorrow and we don't know for Sunday," Mourinho told a news conference in Turin ahead of Wednesday's Champions League clash.

The match in Turin on Wednesday pits Juve's Cristiano Ronaldo against the team he played for from 2003-09.

Serie A leaders Juventus are top of Group H on nine points, with United second on four.

Mourinho said his team had to learn lessons from last month's 1-0 home defeat by the Italian champions and try and start on the front foot.

"We work every day... but the reality is that normally we don’t start matches well, but if we don't start well and we end well, that's fine," he added.

"It's good fun for the fans, but football is 90 minutes and especially when your opponent is strong, if you give 45 minute advantage, or even 20 or even 10, you have a mountain to climb.

"The good thing is that lately, apart from the (last) Juventus match, we were strong enough to climb the mountain and change the match in the last minutes. When you play against a super team, like tomorrow, if you give an advantage away, it's difficult to climb the mountain."

Sign up to our free newsletters

Get the best updates straight to your inbox:
Please select at least one mailing list.

You can unsubscribe at any time by clicking the link in the footer of our emails. We use Mailchimp as our marketing platform. By subscribing, you acknowledge that your information will be transferred to Mailchimp for processing.