In the United States, the match starts at 12:05 p.m. ET and will be broadcast on NBC Sports Network.
"The Premier League is another competition and this is another opponent but it's important, we are fourth in the table and if we want to be at the top of the table and play Champions League next season we have to win these kind of games [against United]".
Mourinho won three Premier League titles in two spells as Chelsea boss between 2004 and 2015, but his relationship with his former employers has been strained by a war of words with Chelsea boss Antonio Conte.More news: Marit Bjorgen caps historic Olympics with more history
"I've never played against Inter since I left, but I've faced Porto, Real Madrid and Chelsea and the feeling is a good one".
After already suffering two losses in the season against the club where he was a three-time champion, losing 4-0 in the league and also going out of the FA Cup quarter-final, both at Stamford Bridge, the Portuguese was desperate to turn it around at Old Trafford.
Manchester United have lost to Newcastle United and Tottenham Hotspur in their last two Premier League games on the road.
'Personally I forgot this mistake, ' said Conte.More news: President Trump blames armed officer at FL high school
Afterwards a beaming Mourinho denied he enoyed the victory more because it was against Chelsea and his nemesis Conte.
"I had great memories with him [Mourinho]", the Brazilian told Sky Sports.
The aggravation of Herrera's muscle injury means the midfielder will miss the next few weeks - and the chance to renew his battle with Eden Hazard.
Manchester United, meanwhile, battled to a goalless draw with La Liga Sevilla in a disappointing performance in Spain.More news: Premier League table: Liverpool displace Manchester United from second position