March 5 (Reuters) - Manchester United ( MANU ) will be without defender Harry Maguire and midfielder Manuel Ugarte for Thursday's Europa League last-16 clash with Real Sociedad, coach Ruben Amorim said, as he seeks to salvage an otherwise dire season.

The pair were left out of an already depleted squad after picking up injuries in last weekend's penalty shootout defeat to Fulham that dumped them out of the FA Cup to compound the misery of lying 14th in the Premier League.

"We are being careful with them because at the moment we cannot afford to lose any more players for a long time," Amorim told a press conference on Wednesday before the Europa League first leg game in Spain.

"We are taking care of them at Carrington (training ground) and they cannot play this game because it will be a greater risk."

The coach, who joined United in November, stressed the importance of balancing youth development with the needs of the squad during a worsening injury crisis.

"I'm trying to cope with everything. When I do my squad, I'm trying to think about every aspect, of the formation of the (new) kids, of the squad and not if it will look really well with the fans and the media," Amorim said.

Altay Bayindir, Tom Heaton, Jonny Evans, Kobbie Mainoo, Luke Shaw and Mason Mount remain on individual rehabilitation programmes.

Lisandro Martinez, who tore his anterior cruciate ligament, and Amad Diallo, who suffered an ankle ligament injury in training, are also sidelined.