The manager told a press conference on Saturday: "As always, we have to wait to make a decision.

"The other day we did not want to risk him and we are in a similar situation tomorrow.

"He's okay, but if he were at 100 per cent, as he has been at other times, he'd play."

The 31-year-old recently became the first player in LaLiga history to reach 400 goals and would bring a boost to a Barcelona side looking for their eighth league win in a row.

Valverde expects a difficult game on Sunday, adding: "It will be a beautiful game, but visiting San Mames is always complicated, it is one of the most difficult games of the season."

The Barcelona manager returns to face the team he led for six seasons on his 55th birthday and will be looking to improve his record as a visiting coach of one win and four defeats in the League.

Valverde will be without midfielder Arthur who picked up a hamstring injury and is expected to return in a month.

The boss added: "(With Arthur) we've lost a player who gives us a control of the game but you can't avoid injuries over the course of the season."

In place of the injured Arthur, Valverde has placed his faith in Philippe Coutinho, who is set to start.

Ousmane Dembele will start for Barcelona while Samuel Umtiti was not included in the starting line-up.

Bilbao manager Gaizka Garitano believes his side have to be at their best tomorrow against top-of-the-table Barcelona.

Garitano said on the club's official Twitter feed: "We will play against the best team there is and it requires us to be at our best.

"We play at home with our people and it's a nice game to try and win against a great team."

The Bilbao boss admitted his side could struggle to have much possession against the style of football played by Barcelona.

He added: "We need to have everyone ready for tomorrow's game. Against Barcelona you always have to have a good match in addition to having a little luck."

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