Manchester United were underdogs to beat Spurs following a 2-0 loss to Mauricio Pochettinio’s men at Wembley earlier this year.
Tottenham appeared to be in control of the cup clash after England midfielder Dele Alli broke the deadlock in the eleventh minute at the home of English football.
However, former Arsenal striker Alexis Sanchez equalised before half-time thanks to his fourth goal for the 20-time English champions.
Spanish midfielder Ander Herrera scored the winner in a 2-1 win against Spurs in the FA Cup final at Wembley last weekend.
Mata was an unused substitute in Manchester United’s FA Cup triumph but the former Chelsea FC star will be hoping to break into the team for the final against his old club.
Writing in his personal blog One Hour Behind about the FA Cup final next month, Mata said:
“The semi-final against Tottenham was the best way to complete a positive week because it gives us the opportunity to play for a very special title.
“I’ve been so lucky to win it twice and I can tell you that it is something different, in a competition with so much history behind, at Wembley…”
Manchester United are in second place in the Premier League table and a long way behind champions Manchester City in the title race.
The Red Devils won the EFL Cup and the Europa League in their first season under Mourinho.
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