Champions-elect Chelsea, who need only five points from the final five games to be sure of their first English league title for 50 years, host neighbours Fulham on Saturday and Liverpool on Wednesday.
"He (Robben) is back for tomorrow," Mourinho told a news conference called to publicise the club's backing for a cancer charity. "It is important because he's a special player and special players are always a plus."
The fleet-footed Robben has played only a few minutes for Chelsea since he broke his foot against Blackburn Rovers on February 2. He returned last month and injured the foot again on international duty with the Netherlands.
Mourinho, who has avoided the limelight recently following a clash with UEFA, said he did not mind when Chelsea clinched the Premier League title, he simply wanted to enjoy the delight of his players when they did.
"It doesn't make any difference where and when, or with a bigger or smaller margin, we just want to get the points we need," the Portuguese coach said.
Opponents were going to make it tough for the London side, he said.
"Nobody wants to lose for us to win the championship. Nobody wants to be part of Chelsea's celebration," he joked.
"The players have been absolutely fantastic. I just look forward to the day when we can be made champions because I want to see their happiness."
RUMOURS UNTRUE
Mourinho said rumours he was considering quitting Chelsea, after he was banned by UEFA for two European games following his criticism of referee Anders Frisk, were untrue.
He was not involved in any contract talks with the club though he did not discount the possibility that his agent might be.
"I have three more years on my contract and I want to stay," he said.
Mourinho, in reflective mood, said that despite their 11-point advantage, the season had been tough with a lot of pressure on a new team and manager.
He had also been stung by some of the criticism.
Chelsea were dubbed boring at the start when he was building defensive strength and the side were grinding out 1-0 wins. He and the team had had to develop something of a siege mentality.
Mourinho's outspokenness deflected attention from the players and allowed them to concentrate on their football.
The team told him they appreciated that, he said, though he had learned during the year he should perhaps avoid reacting too quickly to negative comments.
When they clinched the title, Mourinho said he would slip into the background again.
"When, as I hope, we become champions that's a time to disappear a little bit, a time for the players," he said.
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