Red-hot Barcelona rode on a Ferran Torres double and two assists from Ousmane Dembele to roll over Osasuna 4-0 for a fourth consecutive La Liga win Sunday.

The victory moved Barca into the top three with 51 points, level with fourth-placed Atletico Madrid and five points behind second-placed Sevilla, but with a game in hand over its nearest rival.

Torres opened the scoring 14 minutes into the game with a penalty after Gavi was tripped from behind inside the area.

Seven minutes later, he doubled his tally, receiving a brilliant pass by Dembele in behind the defense before beating the keeper with a delicate finish.

Dembele was unstoppable on the right flank and five minutes later the French winger teed up Pierre-Emerick Aubameyang to net Barca's third from close range.

Substitute Riqui Puig completed the victory when he found the net after collecting a rebound in the 75th minute.

"I’m really happy that we won and are rising," Torres told reporters.

"Our objective is to keep climbing in the standings and keep improving game by game."

Coach Xavi Hernandez seemed happy with the result but believes fighting for the league title is a long shot with his side trailing leaders Real Madrid by 12 points.

"I don't think the league is possible this season, Real Madrid is too far ahead," Xavi said when asked about the importance of next Sunday's El Clasico against the bitter rival at Madrid.

"We need to keep winning and they have to lose three or four games, it's not realistic."

Having dropped as low as ninth in November, when coach Ronald Koeman was fired, Barca is closing in on second-placed Sevilla, who dropped more points in a 1-1 draw at Rayo Vallecano earlier Sunday.

The fight to finish in the top four and secure Champions League qualification is intensifying, with only four points separating Barcelona from Real Sociedad in sixth.

Sevilla was the only team in the top seven who played and did not win this weekend and it is now looking over its shoulders after a sixth draw in the last eight league matches.

Real Madrid, who comfortably lead with 63 points from 27 games, will play at lowly Mallorca on Monday.

Wins for Real Betis, Real Sociedad and Villarreal moved them closer to Sevilla. Fifth-placed Betis has 49 points, Real Sociedad, 47, and Villarreal, in seventh, has 45.