Mauricio Pochettino has confirmed Chelsea forward Christopher Nkunku is dealing with a fresh hip injury which will keep him out of Tuesday's Carabao Cup semi-final first leg against Middlesbrough.
The Frenchman has made four appearances for Chelsea since returning from knee surgery which forced him to miss the first half of his debut year at Stamford Bridge.
Pochettino had previously admitted Nkunku was not fit enough to start Saturday's FA Cup clash with Preston but then ultimately left the 26-year-old out of his squad altogether, sparking rumours of a potential flare-up of his previous injury.
Ahead of the Boro game, Pochettino moved to alleviate fears but conceded he was unsure when Nkunku would return.
"It's not related to his old injury, it's a different problem," Pochettino said. "A small issue in his hip, not in his knee, we are cautious with him because it is six months from his injury, and he was involved in few games. He won't be involved tomorrow, we will see for Saturday. We are not sure, we are going to be cautious.
"Hope it is not a long period. At the moment he is not training, he is doing recovery. Not a big issue."
Reports in France have also claimed that Nkunku's hip injury is not a serious one. It was initially speculated that the forward could feature for Chelsea against Boro, although Pochettino has confirmed otherwise.
Another starter who has been sidelined by injury is goalkeeper Robert Sanchez, who was forced off late in the 2-0 defeat to Everton and has missed the last six games in all competitions.
"We saw him, he came from a scanner and needs to see the doctors, see the scan and the make a decision to progress," Pochettino said of Sanchez. "The evolution, we need to keep a little bit more away from training. After today we will have a clear idea after the scan this morning."
Asked if surgery was needed, Pochettino added: "No, only the pace of the evolution and how he can improve going from doing treatment to starting on the pitch."
