LONDON -- Antonio Conte said he still does not know when David Luiz will be fit to return for Chelsea as he continues to receive treatment for inflammation in his right knee.
Luiz has not featured since last month's 4-0 away win over Qarabag in the Champions League, and the mystery over his injury has fuelled speculation that tension with Conte is the real reason for his absence and that the situation is threatening to bring an end to his second spell at Stamford Bridge.
Last week Chelsea said that Luiz was being treated "day to day" by the club's medical staff for knee inflammation.
Speaking in a news conference to preview Saturday's clash with Southampton, Conte said that remained the case but was unable to shed any further light on when he could come back.
"David has a big inflammation in his knee, and we are trying to solve the situation with the doctor," Conte said of Luiz. "It's important to assess the situation day by day, and to try to solve this problem.
"I don't know when he's able to come back with us but, for sure, with the doctor and the medical department, we are trying to solve this situation. The situation is an inflammation in his knee.
"The player is working apart [from the squad]. In the last days he was out to work in the pool. Today I saw him on the pitch, to try to run a bit, but very, very slow. I think that this is a serious problem, but we hope to solve this problem as soon as possible."
Asked if Luiz is frustrated by the situation, Conte replied: "I think every player is frustrated when he doesn't play, especially when you have an injury. For sure, there is a lot of frustration for the injury. Every player wants to enjoy the training session, to try and put the coach in difficulty with his choices.
"I understand because I was a player. When I was injured, for sure, my feeling was very bad. It was sad. You want to feel very well and then be available for the competition, for the training session, and to be in contention, but injuries are part of their jobs."
Conte will at least have Alvaro Morata to call upon once again. The Spain international missed Tuesday's 3-1 win over Huddersfield Town with a combination of back pain and fatigue, but is available to face Southampton despite dealing with a level of discomfort.
"He's better," Conte said of Morata. "He trained with us two days ago, and also today. He has this pain in his back, but he's in contention for tomorrow's game."
Southampton have won just one of their last eight Premier League matches and were beaten 4-1 by Leicester City on Wednesday, but Conte warned that this will make them more dangerous opponents at Stamford Bridge.
"I can tell you that, for sure, tomorrow the game will be very difficult for us," he said. "Because, for me, Southampton are a really good team. They have a lot of good players, young players but good players with great futures.
"I think I would prefer that Southampton had won the game against Leicester instead of losing in this way, 4-1 at home. I heard the interview post-game from the coach, from Pellegrino, and we must pay great attention. This team are very strong. They're a good team.
"The players are very fast. They can play very well on the counter-attack: Austin, Redmond... Tadic. They have a lot of good players. [Shane] Long, [Sofiane] Boufal... We must pay great attention. Tomorrow, my expectation is to suffer. I have this sensation. We must pay great attention."