Barcelona defender Gerard Pique has apologised for being sent off in the second leg of the Spanish Super Cup but denied insulting the assistant referee.

The ex-Manchester United player, 28, confronted the official during Monday's game against Athletic Bilbao, which they drew 1-1 to lose 5-1 on aggregate.

"I want to apologise because the attitude with which I protested was not the correct one," he tweeted. 

"At no point did I direct any insult towards the assistant referee."

The Royal Spanish Football Federation (RFEF) is expected to announce Pique's punishment on Wednesday.

Barcelona begin their bid for a sixth La Liga title in eight years at Bilbao on Sunday.

/By BBC/