The Real Madrid coach hit back at comments made by Andres Iniesta, in which the Spain international said he was surprised by Mourinho's treatment of Madrid goalkeeper Iker Casillas.
"[Iniesta] can think what he likes, but I would say to him that without Messi his team is so different and that is why they did what they did in the semifinals of the Champions League," the 50-year-old told reporters.
The former Chelsea and Inter boss then took responsibility for his team's failure to meet its objectives this term.
"We want to finish the league in second place - but second place is not enough," said the two-time Champions League-winning coach. "I haven’t been strong enough or persuasive enough as a coach to reach our objectives."
Mourinho was keen to add that his career at Madrid may not definitely be over, however, despite strong speculation linking him with a summer exit.
"If I think, and the boys think, that I can go on giving something more, I will continue [at the club]," he added.