Victor Ruiz put through his own net to give the Basque's the lead after just nine minutes.

It was 2-0 in the 33rd when Ander Capa scored with a header after Claudio Bravo had saved from Asier Villalibre's header.

Iker Muniain netted a third for the home side on 59 minutes after Bravo saved his first effort but the forward scored from the rebound.

Alex Berenguer added a fourth from Yuri Berchiche's cross in the 68th, and it could have been worse for the visitors if not for the heroics of goalkeeper Bravo.

"This is the result we were looking for," said Athetlic forward Villalibre, who played a key part in all four goals.

"A forward always looks back on the chances he didn't take but I'm just happy for the points.

"Every win counts the same in terms of the points you earn but the timing of this victory really helps us."

Athletic are on 12 points, 11 behind leaders Real Sociedad but with a game in hand, while Betis drop to 12th having lost four of their last five league games.

"It's unusual for us to win by four goals," winning coach Gaizka Garitano said.

"In other games we have got into good positions but not taken our chances."

Australian Associated Press