Middlesbrough defenders Dael Fry and Daniel Ayala will miss the rest of the season with injuries and their recovery will continue through the off-season.
Centre-back Fry, 21, tore his hamstring in training and Boro boss Tony Pulis expects him to be absent for up to 12 weeks.
Meanwhile, Ayala, 28, was withdrawn in the win over Hull with what scans showed is a "serious ligament injury".
"It's a big blow," Pulis said of Fry's injury setback.
"He's been growing in confidence and he's played in all sorts of positions.
"We've been delighted with his progress; I thought he was our best player last weekend.
"Dani has serious ligament damage and he won't be back this season either."
Boro now have some major defensive absentees, with George Friend also unavailable, as they chase a Championship play-off place.