Missing Leo: Barcelona stumble to first league defeat
December 2, 2013 -- Updated 0946 GMT (1746 HKT)
Iker Muniain celebrates his 70th minute winner for Athletic Bilbao against Barcelona in the San Mames.
- Barcelona lose first La Liga game of the season
- Beaten 1-0 by Athletic Bilbao at San Mames
- Goal by Iker Muniain in second half gives Bilbao famous victory
- Juventus stay top in Italy with 1-0 win over Udinese
(CNN) -- Without talisman Lionel Messi, Barcelona slipped to their second defeat in a week as a 1-0 reverse at Athletic Bilbao Sunday blew the Spanish title race wide open.
Already qualified for the Champions League knockout stages, their 2-1 midweek loss to Ajax Amsterdam could be forgiven, but Iker Muniain's 70th minute winner for Athletic has far greater significance.
It was Barca's first league reverse of the season and left them level on points with Atletico Madrid with arch-rivals Real Madrid snapping at their heels a further three points adrift.
Lionel Messi's messy tax scandal
Lionel Messi breaks goal scoring record
Athletic, who are unbeaten at their new San Mames stadium, have moved up into the fourth Champions League spot with the victory.
Read: Is Messi at risk of burning out?
Muniain might have put them ahead in the first half but he wasted a great chance from close range, while Barcelona offered little in reply.
Brazil's Neymar was kept quiet but just after half time he burst through only to be pulled back by home midfielder Ander Iturraspe, who was lucky to escape with a yellow card.
But the men from the Basque country remained a constant threat and Markel Susaeta crossed for Muniain to slide home his decisive goal.
A second should have followed but Gaizka Toquero headed a cross straight at Barcelona goalkeeper Jose Manuel Pinto, who made a reaction save.
Barcelona coach Gerardo Martino flung on Sergi Roberto and Pedro as late substitutes, but to no avail.
Messi was confined to the sidelines for the second time this season last month with a hamstring injury which is set to keep him out of action until January, missing at least two more La Liga games.
Read: Bale fires first Real Madrid hat-trick
Meanwhile in Italy, champions Juventus went three points clear of early pace setters Roma with a 1-0 win over Udinese Sunday.
It took an injury-time header from Spain striker Fernando Llorente to grab the three vital points as he headed Stephan Lichsteiner's shot past Zeljko Brkic.
Juve had plenty of chances to wrap up their 12th win of the season and sixth in a row, but were frustrated by dogged defense and poor finishing until the last gasp strike.
Earlier, Roma were held to their fourth draw in a row, 1-1 away at Atalanta.
Napoli, who are in third, nine points adrift, travel to Lazio Monday.
Fourth placed Inter Milan failed to make up ground as they were held 1-1 at home to Sampdoria.
Renan scored a late leveler for Sampdoria after Fredy Guarin had given Inter an 18th minute lead at the San Siro.
Today's five most popular stories
Part of complete coverage on
December 16, 2014 -- Updated 1123 GMT (1923 HKT)
After 20 years, more than 300 goals and a host of major honors, Thierry Henry has called time on his glittering football career.
December 19, 2014 -- Updated 1014 GMT (1814 HKT)
They do things differently at Sociedad Deportiva Eibar, up in the mist-cloaked valleys of the Basque country. And it is working.
December 10, 2014 -- Updated 1353 GMT (2153 HKT)
He might be struggling to score goals for Liverpool, but Mario Balotelli's cheeky tweet about the British monarch hit the spot during the World Cup.
October 28, 2014 -- Updated 1253 GMT (2053 HKT)
They splash the cash on the world's best players, now Real Madrid are giving the Bernabeu the same treatment with a bling makeover.
October 27, 2014 -- Updated 1309 GMT (2109 HKT)
Football world mourns South African captain Senzo Meyiwa who was shot and killed during a botched robbery in a township near Johannesburg.
October 21, 2014 -- Updated 1348 GMT (2148 HKT)
From the ancient ruins of Rome, a new empire rises. But the eyes of the city's newest gladiator light up at thoughts of the Colosseum.
October 21, 2014 -- Updated 1622 GMT (0022 HKT)
Once part of Germany's largest Jewish sports club, now he's the first ISIS suspect to stand trial in a country left shocked by his alleged radicalization.
October 17, 2014 -- Updated 1411 GMT (2211 HKT)
One goal in eight matches for new club Liverpool, and dumped by the Italian national team -- Mario Balotelli has yet to shine on his English return.
October 18, 2014 -- Updated 1819 GMT (0219 HKT)
Should a convicted rapist, who has served their time in prison, be allowed to resume their old job? What if that job was as a high-profile football player?
October 16, 2014 -- Updated 1247 GMT (2047 HKT)
After 10 years of golden glory, it's easy to see how Lionel Messi has taken his place among the football gods.
October 16, 2014 -- Updated 1034 GMT (1834 HKT)
When will the tears stop? A leading Italian football club is pursuing a new direction -- under the guidance of its new Indonesian owner.
October 13, 2014 -- Updated 2241 GMT (0641 HKT)
Norwegian 15-year-old Martin Odegaard is the youngest player ever to feature in a European Championships qualifying match.
October 10, 2014 -- Updated 1310 GMT (2110 HKT)
After revolutionizing cricket with its glitzy Twenty20 league, India has now thrown large sums of money at a new football venture.
October 2, 2014 -- Updated 1453 GMT (2253 HKT)
Get ruthless. That is Rio Ferdinand's message to soccer's authorities in the fight to tackle the scourge of racism.
September 10, 2014 -- Updated 1328 GMT (2128 HKT)
He's just 15 and the world is seemingly already at his feet. Norway's Martin Odegaard is being sought by Europe's top clubs.