Los Blancos looked set to suffer a massive upset as Valencia led 2-1 until the Portugal star's magnificent backheel volley late in the 92nd minute ensured his side took a point from the game, even if they failed to capitalise on the slip-ups of Atletico Madrid and Barcelona earlier in the weekend.
Madrid are now five points behind league leaders Atletico with a game in hand over their rivals, and the Italian coach believes that, had it not been for Ronaldo's goal, the Spanish giants would have crashed out of contention altogether.
"Ronaldo’s goal is very important because losing this game would have meant that we lost the league," he told reporters after the game.
"Like I’ve said before, the league will be decided in the last game. It was a tough week for all the three teams.
"The team started the match well but it became more difficult to play with the same intensity. We lost a good chance to advance in the league but it’s not over yet.
"It’s normal that the team is not happy because we tried to win and we couldn’t do it. We will fight until the end. Chelsea, Atletico and my team weren’t at their top physical shape and we paid the price for that."