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Barcelona faced a must-win match on Sunday at Villarreal. Lionel Messi led his team to a 4-1 win that keeps Barca's La Liga title hopes alive. The Catalan club entered the day trailing Real Madrid by four points, but that deficit became seven points Sunday morning following Real's 1-0 win at Athletic Bilbao. Real captain Sergio Ramos scored his 22nd straight penalty kick in the 1-0 win. Ramos also scored a winning penalty kick in Los Blancos' previous match which was a 1-0 win over Getafe. 

For Barca, going to Villarreal seemed like it was going to be more of a challenge than it was. Barca got an own goal three minutes in before Gerard Moreno's equalizer in the 14th minute. But it would be all Barca from there. Luis Suarez, Antoine Griezmann and Ansu Fati all scored for Barca, with Messi delivering the assists on sensational strikes by Suarez and Griezmann. 

The goal from Griezmann was a perfect chip off a cheeky backward pass by Messi.

The victory for Barca sees the club still trailing by four points with four games remaining on the season.

Here's everything to know about the race for the trophy.

Standings

Real has a four-point lead, which means a lot can change in just one match.

PositionGames playedPointsGoal differential

1. Real Madrid

34

77

+41

2. Barcelona3473+42

Remaining schedule

Here's a look at each team's remaining matches. Real has the tougher schedule with three matches against the top seven while Barca has two. Barca has the easier slate, and Real has less days of rest. Advantage Barcelona?

Matchday 34: Barcelona 4, Villarreal 2; Real Madrid 1, Athletic Bilbao 0
Matchday 35: Barcelona vs. Espanyol (7/8); Real Madrid vs. Alaves (7/10)
Matchday 36: Barcelona at Real Valladolid (7/11); Real Madrid at Granada (7/13)
Matchday 37: Barcelona vs. Osasuna; Real Madrid vs. Villarreal
Matchday 38: Barcelona at Alaves; Real Madrid at Leganes

What if they finish the season tied atop the table?

In most leagues, the first tiebreaker is goal differential. That isn't the first tiebreaker in Spain, and that won't come into play if the two are tied on points come season's end. In La Liga, the first tiebreaker is head-to-head points, meaning the amount of points the teams earned against in each other this season in their two meetings.

In their first match, Barca and Real drew 0-0. In their second meeting, Real won 2-0. That means in two matches, Real earned four points (a win and a draw) while Barca took one point (a draw and a loss).

Because of this, if the two clubs finish the season tied on points, the title goes to Real Madrid.