Ruben Amorim's United ran riot at San Mames, as Casemiro's header and a brace from Bruno Fernandes helped them secure a comfortable first leg win and Bilbao have a mountain to climb in the battle to reach this month's final. But despite the three-goal margin, Valverde is not giving up hope.

The Spaniard believes his side can spark a dramatic comeback and still go through to the Europa League final, but he will be hoping he has his best players available.

One player that won't be available, however, is Dani Vivian, who will be suspended for the match against United. The defender was sent off for denying a goalscoring opportunity in the first leg at the San Mames and will now serve a one-match ban in a huge blow for the Basque outfit.

In terms of injuries, Sancet, who missed the first leg with a muscle issue, is fighting to get back fit and could return to face United in the second leg. Meanwhile, Spain star Williams played 79 minutes in Bilbao before being substituted, though there were concerns over his fitness beforehand.

Now, Valverde has offered a fresh update on Sancet and Williams going into this Thursday's second leg. Speaking after Athletic Club were held to a goalless draw against Real Sociedad - another team that United have beaten in the Europa League this season - the ex-Barcelona boss said: "Sancet is doing quite well, and Nico, week by week, we're trying to get him back on his feet. We'll see what's coming next."