MADRID (AP) — Barcelona, Real Madrid, and Atletico Madrid continue their duel at the top of the Spanish league, with each of the title hopefuls looking to take advantage of any slip-ups and open up a gap.

Barcelona and Atletico go into the 25th round off the back of morale-boosting Champions League victories, while Madrid will prepare for its continental matchup at Schalke.

Barcelona is technically top on goal difference. Atletico is at Osasuna on Sunday.

Here are five things to know about the Spanish league this weekend:


NEYMAR'S FRUSTRATIONS: Neymar's return from injury has given Barcelona a boost, despite the Brazil forward feeling some of the pressure concerning the investigation into his contract and transfer from Santos last summer. Neymar took to social media to blast his former club and support his father, who has come under scrutiny for reportedly earning 40 million euros ($55 million) from the 57 million euro (then $77 million) transfer. "I'm tired of this crap. I'm a fan of my father and I'll always be grateful for having taken me to where I am today," Neymar wrote, "and if he made millions over that, what's the problem?" Prosecutors in Spain allege Barcelona avoided paying 9.1 million euros ($12.5 million) in taxes through Neymar's transfer, which the club denies. Former president Sandro Rosell is also being investigated over the deal. Barcelona faces a tough trip to Real Sociedad, which is just four points off fourth place and the league's final Champions League qualifying place, on Saturday.

LOOKING TO BALE: Neymar isn't the only new Spanish league recruit having problems adapting. Madrid forward Gareth Bale's season has been wracked by injuries, and when he is playing he's had few bright spurts. Former Madrid coach and sport director Jorge Valdano chalks up Bale's form to nerves. "Bale has a rare anxiety because you don't notice it in his game," Valdano said. "When you're anxious, you play at a faster pace than what you normally do, but he seems absent. The team is bailing him out." The world's most expensive player, who cost Madrid a reported 100 million euros ($132 million), has scored two goals this calendar year.

NO RONALDO, NO MATTER: Real Madrid has shown no ill effects from the absence of Ballon d'Or winner Cristiano Ronaldo, who serves the final game of a three-match ban on Saturday against Elche. Madrid is unbeaten in 25 games in all competitions, stretching back to October, with Ronaldo going into Tuesday's Champions League match fresh after sitting on the sidelines for two weeks. Madrid will be without midfielder Luka Modric to a ban when its plays at its Santiago Bernabeu Stadium.

CELTA'S LITTLE SECRET: Celta Vigo should be thanking Barcelona for its mid-table position after earning promotion to the topflight. Playmaking midfielder Rafinha arrived in Vigo on-loan from the Spanish champions and has been instrumental in directing Celta's attack with his vision, deft touch, and forward's instinct. But Rafinha, whose brother is Thiago Alcantara of Bayern Munich, is already looking to get back to Barcelona once the loan ends, according to his father and agent Mazinho, who helped Brazil win the 1994 World Cup. In the meantime, the 21-year-old midfielder can continue his and Celta's upstart season — the Galician club is 11th — at home to Getafe on Saturday.

ODD FINES: The Spanish league's disciplinary committee's procedures for imposing fines is under scrutiny following a number of contrasting, and baffling, sanctions. Atletico was fined 600,000 euros ($820,000) after Cristiano Ronaldo was struck in the head by a cigarette lighter, while the league wants to pay homage to Villarreal's fans despite one throwing a tear gas canister onto the Madrigal field during a 2-0 loss to Celta. Meanwhile, second-tier Real Jaen striker 'Jona' was slapped with a 2,000 euros ($2,750) fine for displaying a shirt with words of support for world child cancer day, with children battling the disease in attendance. "I just wanted to get them smiling," Jona was quoted as saying in sports daily Marca. Spanish league president Javier Tebas is quoted as saying the fine should be dropped.


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