United fans protesting against the club's American owners, the Glazer family, stormed into the stadium which was closed to fans due to COVID-19 restrictions.
Greater Manchester Police (GMP) said two officers were injured with one requiring hospital treatment after he was attacked with a bottle and suffered slash wound to his face.
Real said on Monday the France international had hurt his right thigh during Saturday's 2-0 win over Osasuna in La Liga, in which he was substituted at halftime.
Varane missed both legs of Real's Champions League quarter-final against Liverpool due to a coronavirus infection but completed 90 minutes in last week's 1-1 draw at home to Chelsea.
"Let me try to win at Crystal Palace... United is an extraordinary team arriving in the last two months in their best form of the season and we need five points to be champions," Guardiola, whose side beat Paris St Germain 2-1 in the Champions League in midweek, told reporters on Friday.
"All we can do now is recover as well as possible from the physically and mentally tough game we played in Paris. It is our sixth game in a row away. It is a lot of travel and we are tired in many aspects.
It would be their fifth Premier League title in 10 seasons and a third in five since Guardiola brought his special brand of football to the Etihad.
That performance in Paris put City on the brink of a first Champions League final, and Guardiola in sight of delivering the European crown club owner Sheikh Mansour hired him to deliver.
"The financial incentive for the clubs is plain to see, with a multi-billion dollar package at the heart of the scheme, albeit it would forever break the integrity of the club game," said Neil Wilson, chief market analyst at Markets.com.
They were missing key players in Eden Hazard, Raphael Varane and Sergio Ramos for the quarter-final first leg but dominated the midfield thanks to their long-running trio of Casemiro, Luka Modric and Toni Kroos, the foundation of their three consecutive Champions League triumphs.
Watching Real beat the Premier League champions so comfortably, it was easy to forget what a chaotic season it has been.
A chastening 3-1 defeat in the first leg of their quarter-final in Spain on Tuesday has given the Premier League side a mountain to climb if they are to reach the last four.
Liverpool face Madrid in Spain later on Tuesday before next week's return fixture at Anfield, where the Merseyside club have struggled in the Premier League this season, with matches taking place without fans due to the COVID-19 pandemic.
Benitez, who managed Liverpool from 2004 to 2010 and had a short spell at Madrid, said it was crucial the English side get a goal in the first leg.
The first leg will take place on April 7 at Estadio Ramon Sanchez-Pizjuan with the return fixture scheduled for April 13. The prize for the winners will be a clash with Real Madrid or Liverpool.
Spain said earlier this month it would lift a ban on travel from Britain on March 30. The ban had started in December, over concerns about a British strain of the new coronavirus.
Strikers Yussuf Poulsen and Alexander Sorloth have been in superb form in recent weeks along with Christopher Nkunku, and Leipzig have won seven of their last eight Bundesliga games.
"I am happy that our attack in the past months has had a big influence in our wins," Nagelsmann told.
Chelsea beat champions Liverpool 1-0 on Thursday to climb to fourth in the table, a prospect that looked bleak when Lampard was dismissed with the team in ninth place.
"It's proven that Chelsea is an organisation and a club that has everything that you need to be successful as a coach and as a football team, so now it's my job to bring out the very best of myself, together with the team.
Former Liverpool defender Jamie Carragher said the Merseyside club must take action in the summer transfer window to address their goal-scoring problem.
Goalkeeper Alisson was granted compassionate leave following the sudden death of his father last week and subsequently missed the 2-0 win over Sheffield United on Sunday.
"So Ali trained now for the full week and yes we should expect that he is able to return," Klopp told a news conference on Wednesday.
Chelsea are fifth in the table with 44 points from 26 games - a point below fourth-placed West Ham - and have not lost in seven league matches since Tuchel replaced club great Frank Lampard in January.
"It's of big importance, I hope we can show up with the same mentality and attitude like the tough challenges we've had.
Liverpool's first league win since beating West Ham United 3-1 on the last day of January leaves them in sixth position in the table on 43 points, one behind their next opponents Chelsea. Sheffield United remain bottom on 11 points.