LISBON, Portugal — Jose Mourinho won't let his past rivalry with Pep Guardiola get in the way of his new career at Manchester United.

With Guardiola taking charge at Manchester City, the pair will face off in the Premier League next season. They previously were adversaries when Mourinho was at Real Madrid and Guardiola at Barcelona.

"I was with Pep in a league where the champion was either me or him, either Real Madrid or Barcelona," Mourinho said Tuesday. "In that kind of situation, individual battles make more sense because they can affect the outcome (of the title race). If in the Premier League I were to focus on him and Manchester City, and he were to focus on me and Manchester United, someone else would be champion."

Mourinho, who was at Lisbon University to give a lecture, said he couldn't speak about his new club but remarked that he wouldn't be taking any player from Portugal to Old Trafford.