It's a busy night for football fans across Manchester tonight.
Manchester City travel to Germany where they face Hoffenheim in Group F of the competition.
And United play hosts to Spanish club Valencia in Group H at Old Trafford Manager Jose Mourinho doesn't believe his job is on the line if results go against him this week.
They face Newcastle at the weekend in the Premier League.
The club have made their worst start to a league season in 29 years. Mourinho says it's a big week.