The Manchester United boss twice questioned the United and England centre-back’s bravery during the season.
But last night Smalling revealed he had played on with what was later discovered to be a broken toe.
And he had needed two injections to get him through the 4-0 defeat at the Portuguese coach’s former club Chelsea in October.
“I think in the Chelsea game I proved that I can play with the injections,” said the 27-year-old, who has declared himself fit to face Scotland in the World Cup qualifier on Saturday.
“I had a couple of injections because you want to play that game. Soon after that it got worse and that was when I had to have the lay-off.”
After Smalling and fellow defender Luke Shaw pulled out of a game against Swansea in November, Mourinho said: “We have players with problems, but we have on the pitch players with problems.”
The United boss went on the attack again in April when he complained “cautious” Smalling and fellow Englishman Phil Jones had not heeded his appeal to be brave after they missed the derby against Manchester City.
Mourinho’s criticism seemed harsh as Smalling had only come out of a protective knee brace a week earlier.
“I don’t think I’ve got anything to prove,” insisted Smalling. “He knows my character, he knows what type of player I am and that’s not changed.
“You always want to push yourself because you don’t want to let the players or the fans down because you train with them everyday. It’s just been an unfortunate season with injuries.
“All of us professionals we want to play. No player wants not to play.
“I played on and there was obviously a break [in the toe]. Obviously he didn’t know the full extent at that time. You just keep playing until literally physically you can’t and that was the story with the break.”
Starsport revealed last month Mourinho is ready to listen to offers for Smalling this summer.
He confirmed his boss had not apologised for doubting him, but said he understood why he had lashed out.
“He was just as frustrated as us who want to be on the pitch,” said London-born Smalling.
“But I don’t think he knew the full picture then and once it was cleared up it was all good.
“When I’m sitting down with the manager and the medical staff we set out a timeline and then we try to shave it and push and push.
“The manager has shown his frustration, but we are just as frustrated. They are always trying to push us as quick as we can.
“All managers are demanding. It’s good when he shows that frustration because it shows he wants you back out on that pitch.
“If he wasn’t interested, I think he would just leave you alone and he wouldn’t say any of these things.
“So I take it as a positive, as a challenge to get back as quick as I can – which I would have done anyway regardless of whatever was said.”
