An investigation into "abnormal" betting behaviour for Real Sociedad's 2-1 La Liga win over Rayo Vallecano has been launched by the league's governing body.

The result at Anoeta on Sunday denied the visitor the chance to move out of the relegation zone ahead of the final game of the season.

La Liga president Javier Tebas confirmed there had been "abnormal behaviour" in relation to bets placed on the match.

However, he added: "That we've started an investigation means nothing. We investigate every type of rumour. They can end up being true or not."

The loss was Rayo's third in a row and Paco Jemez's men, who are a point adrift of safety, face relegated Levante on the final day.