The Portuguese was sacked by United just under a year ago after overseeing a poor start to the 2018-19 season:
He returned to management late last month when he was appointed Mauricio Pochettino's successor, and he heads back to Old Trafford looking to extend his record as Spurs manager to four wins from four.
Despite the fact Mourinho was sacked by United, he said ahead of Wednesday's clash that he was "happy" at the club for two-and-a-half seasons, and he is hoping for a positive reaction from the Old Trafford faithful:
"Tomorrow I go back as a coach of the team that is going to try and beat Manchester United and that maybe gives a different perspective.
"I expect there is respect shown towards me, but I understand what they want is exactly the opposite of what I want—I want Tottenham to win, during the match of course I expect them to forget me, and I expect them to support their team to try and get the result they want."
He added, per Declan Olley of Sky Sports:
"I'm not a villain; I'm not an enemy, but I am the coach that is trying to win against Manchester United. That's the way I think they are going to look at me. [Ole Gunnar] Solskjaer is the guy that is trying to win the game for United fans, so of course, they are going to support him and not support me."
Spurs and United have both made poor starts to the 2019-20 season.
Back-to-back wins under Mourinho in the Premier League have moved Tottenham up to fifth in the table, but they are still six points off the top four and will be leapfrogged by United if they lose at Old Trafford:
Both sides are already effectively out of the running for the title, and the best they can aim for in the league is to break into the UEFA Champions League spots.
United and Spurs will both be hopeful of winning silverware, though, in the cup competitions.
One of the few criticisms that could be levelled at Pochettino in his successful tenure as Spurs boss is that he never won a trophy.
Mourinho is a habitual trophy winner, most recently leading United to a UEFA Europa League and League Cup double in 2016-17.
He believes, despite their current problems, United could repeat that success in the current campaign:
"These are things they [Manchester United] can do this season too. They can win the Europa League, they’ve qualified for the knockout. They can win the Carabao Cup as they are still in the competition. They can win the FA Cup, they’ve got Wolves in the first round (third round). They can achieve these targets."
Spurs confirmed ahead of their visit to Manchester the four players who will be absent from the clash through injury:
In the corresponding fixture last season, when Mourinho was still in the Old Trafford dugout, Spurs beat United 3-0, but Solskjaer then oversaw a 1-0 win for the Red Devils in the reverse clash in January.
Historically, Spurs have a poor record at Old Trafford in the Premier League era having won there just three times in 27 seasons, but all of those victories have come since 2012.