The United boss made eight changes to the team that saw off Celta Vigo in the Europa League on Thursday to set up a final against Ajax on May 24, and saw his side beaten 2-1 to end their top-four hopes.
United now need to beat Ajax in Stockholm to secure Champions League football for 2017-18, but Mourinho has stressed he did not gamble by throwing in the towel domestically.
"When people say we gambled by going to Europa League, we did not gamble," Mourinho told Sky Sports.
"You cannot play two big competitions with 15 players. It was compulsory.
"The ones that needed to play 90 mins got to play, we got no injuries. At the moment, the Premier League matches are the ones we do not want to play.
"I do not want to think about next season - I want to think about the final we have to play in."
United put in an underwhelming performance at White Hart Lane, but Mourinho was nonetheless pleased with what he saw.
"After 2-0 we had to bring a bit more quality to the team, we brought more balance," Mourinho added.
"We put players back in the right positions.
"I am happy, I am fine with what we had in terms of individual performances.
"The two goals conceded were bad."