Ernesto Valverde is not committed to entering the January transfer market despite Barcelona's dwindling defensive reserves.

Barca host Sporting CP in the Champions League on Tuesday, with their spot in the knockout stages as Group D winners already secured.

That might be just as well for Valverde, who only has Gerard Pique and Thomas Vermaelen to choose from as fit senior centre-backs after Samuel Umtiti suffered a hamstring injury during Saturday's 2-2 draw against Celta Vigo.

The France centre-back joins Javier Mascherano in the treatment room – the veteran defensive player who recently spoke of his time at Camp Nou coming to an end.

Mundo Deportivo has since reported that Mascherano has put in a transfer request, with his eyes on a January move to the Chinese Super League and increased playing time ahead of Argentina's 2018 World Cup campaign.

Speaking ahead of the Sporting match, Valverde played down his transfer plans and insisted Mascherano remained an important member of the Barcelona squad.

"The transfer window hasn't arrived yet. We've been talking about the winter transfer window since August," said the former Athletic Bilbao boss, who batted back questions regarding a purported swoop for Colombia international Yerry Mina.

"When it comes we will talk about the winter transfer window. We are still counting on Mascherano. He is a member of the team, is committed to Barcelona and has been for a long, long time.

"I can't talk about hypothetical conversations really. I'm happy with Mascherano. I want him to be here with us. I've not got concern about him."