|Mourinho had not lost a home match since February 2002 [AFP]
Real Madrid's hopes of catching Barcelona are fast fading after Sporting Gijon scored a late winner at the Bernabeau in Spain's Primera Division.
Miguel De las Cuevas's 79th minute winner ended Mourinho's remarkable nine-year unbeaten home league record on Saturday.
The last time Mourinho failed to take points at his home ground was when FC Porto lost to Beira Mar 3-2 back in February 2002.
"We have lost a large part of the league,'' said Madrid defender Sergio Ramos.
"Being realistic, there are very few points left.''
Barcelona moved eight points clear with a 1-0 win at Villarreal.
In a tense game at the Bernabeau, Ricardo Carvalho had a goal disallowed two minutes into the match when the referee ruled that the ball had gone over the byline.
Sporting quickly settled down in defence and succeeded in frustrating the repeated incursion of Angel Di Maria down the left flank.
Madrid striker Gonzalo Higuain returned to the pitch for the first time since injuring his back last November as a substitute for Esteban Granero in the 57th, and three minutes later tested Colinas with a hard strike inside the area.
But Madrid failed to react and De las Cuevas did not waste his chance to silence the Bernabeu crowd in the 79th minute.
A downbeat Mourinho admitted after the match that Real's title hopes now look slim:
"Mathematics say the league is not lost but objectively speaking if the gap goes from five to eight points we can say that it''s almost impossible," Mourinho told a news conference.
The Special One will hope to get back to his winning ways at home with Tottenham visiting for the quarterfinals of the European Champions League on Tuesday.
At El Madrigal Stadium, Barcelona's Gerard Pique controlled a ball flicked on by Sergio Busquets with his chest that put him through the defence before rifling it past Villarreal goalkeeper Diego Alves for the 66th-minute winner.
"It is an important step forward, there are eight weeks left, but it is not over,'' said Pique.
Barcelona's 81 points in 30 weeks set a league record, and their 28th undefeated league game extended a club record that had stood at 26 since 1973-74 season.