The discussions are in the early phases, but his name has been brought up internally as they evaluate whether to formalize their interest.
Spurs are aware United are not actively seeking to sell him, but are aware that the club has previously shown a willingness to entertain offers if the price is appropriate.
Mainoo is among several players Spurs are considering as they look to reshape their midfield - and his adaptability could be crucial as they aim to bolster various parts of the squad.
The goal is not just to add depth, but to recruit players who can immediately improve the starting XI - ideally with Premier League experience, quick thinking, and the ability to adjust swiftly to Thomas Frank’s system.

Tottenham has already made a decisive move in one instance, activating Morgan Gibbs-White’s release clause at Nottingham Forest. They are now waiting to see how that situation develops - with Forest pursuing legal action regarding how they discovered his release clause amount.
Gibbs-White is viewed as a strong stylistic match, and they hope it will materialize - but they must be ready for any outcome.
Additionally, they are looking to sign a more defensively oriented player.
Joao Palhinha is further along in the recruitment process. Spurs have been informed that Bayern Munich would prefer a permanent transfer over a loan, which could differentiate them from other interested clubs Fulham and Manchester United, who would favor a temporary arrangement.
Palhinha is not actively seeking a move but has limited clarity about his role for the upcoming season and is keeping his options open.
The club’s dream signing remains Adam Wharton, who they hold in very high regard. However Crystal Palace is setting the asking price extremely high - some sources indicate over £80 million - so even with their new ambitions, Spurs might face challenges.
Other alternatives have been considered, including Joao Gomes from Wolves and Carlos Baleba of Brighton, but neither appears straightforward as their clubs are reluctant to sell.
Juventus player and former Aston Villa man Douglas Luiz has also been mentioned, and he is seeking opportunities in the Premier League, but as of Tuesday night, there had been no significant progress.
Tottenham may even have additional names on their list - as they aim to create surprises this summer.
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