The dropped points at Depor's Riazor stadium enabled Barcelona to stretch their lead at the top of La Liga to seven points with 25 games played after the champions won 3-0 at Real Mallorca in Saturday's earlier kick-off.
Mourinho, whose side drew 1-1 in their Champions League last-16, first leg at Olympique Lyon on Tuesday, told a news conference it would have been easier on Real if they had been allowed to play Depor on Sunday.
"I don't know what would have happened if we had played on Sunday but it would have been fairer," the Portuguese said.
"We could have given an extra day off to those who were most tired, we could have trained an extra day," he added.
"The calendar is set by people who know what they are doing. They do what they want and they will carry on like that."
Real, who twice struck a post late on, face a stiff task to catch Barcelona and end their great rivals' two-year reign as Spanish champions.
However, Real director general Jorge Valdano said it would be absurd to give up on the title with 13 matches remaining and 39 points still available.
"Nobody gives up on the league in February so we will keep on fighting and see if we have a bit more luck in the next few matches," the former Argentina international said in a television interview.
"The team played with a lot of intensity as usual but we were unable to find the net," he added. "We weren't clinical enough in front of goal and we were also lacking in luck."
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