Four points ahead and with two games left, Barcelona are in pole position to win their 23rd Liga title. Real Madrid are the closest challengers and the only team that can mathematically swipe the crown from the Blaugrana.
Barcelona play Atletico Madrid at the Calderon first, in what should be a tough test. Afterwards, Deportivo La Coruña come to the Camp Nou to finish off the league season.
Real Madrid, on the other hand, first must travel to face Espanyol and then host Getafe. They do not control their own destiny, but they do own the tiebreaker against Barcelona by nature of a better-head-to-head record.
That means that if both teams finish level on points, Real Madrid are champions. However, that's not the likeliest scenario. Barcelona have several ways of clinching the title.
The first is the most straightforward - win at least one of the remaining two games and Barcelona are out of reach. They are champions in that case, regardless of what Real Madrid do.
Alternatively, Barcelona could draw both games, or draw one game and lose the other, and still be champions, so long as Real Madrid do not win both of their games.
If Barcelona lose both games, then Real Madrid will be Champions if they win one game and then draw or win the other. This means Real Madrid cannot be champions if they lose both games, no matter what happens to Barcelona.
To put things in more immediate focus, Barcelona can become champions against Atletico Madrid, one week early. Win the match, and they are champions right then and there. Draw, and they are champions if Real draw or lose. Lose, and they are champions if Real lose.