Manchester City are likely to be without the services of Vincent Kompany for a while longer after Manuel Pellegrini revealed his influential captain may not be in a position to return until the latter part of the 2015/16 Premier League season. Due to persistent calf trouble, he has not started a match for the title contenders since a goalless draw at Aston Villa in November 2015, and will not feature against Everton this week.

The Belgian centre-back did appear to be back on track as he was introduced as a second-half substitute in a 4-1 thrashing of struggling Sunderland on Boxing Day. However, that particular comeback lasted all of just nine minutes before he limped off in frustration, replaced by Martin Demichelis.

"It's difficult to know," Pellegrini was quoted as saying by The Guardian when asked about a return date for the player. "We are still trying to find out the reasons for so many injuries. I'm not so sure, maybe the last part of the season."

Much of the trouble with Kompany's latest absence appears to stem from the fact that it remains uncertain as to exactly what is causing the issue to recur. In a latest press conference transcript released on the official club website, his manager added: "Vincent tried a lot of different things to try and find the cause of the injury so we have no update at this time."

If Kompany were to be sidelined for several more weeks, he would miss a number of crucial matches for his club during the title-run in. Pellegrini's side can book their place in the Capital One Cup final this month, while they face Leicester City and Tottenham Hotspur in February before meetings with Liverpool and Manchester United in March. There is also the small matter of a two-legged Champions League round of 16 tie against Dynamo Kiev to come.

The Citizens host Everton at the Etihad Stadium on 13 January hoping to capitalise on any potential slip-ups elsewhere, as rivals Arsenal and Leicester face tough trips to Liverpool and Tottenham respectively. Yaya Toure and David Silva are expected to play after being rested for the FA Cup third-round victory at Norwich, but Eliaquim Mangala, Fernandinho, Samir Nasri and Wilfried Bony all remain in the treatment room with Kompany.

"It was good to rest both of them as they're in the squad list for tomorrow – we'll see who will be in the XI but we have to play two games close together so we'll see, Silva is 100% fit – maybe it's a risk for him to play Wednesday to Saturday," Pellegrini said.

"Kompany, Mangala, Fernandinho, Nasri and Bony – those five players are injured and not fit for tomorrow's game. Mangala tried to work yesterday with normality but he couldn't. He had some pain still in his muscle – for him, it's best to wait a bit more. It's the same for Fernandinho and Bony. For Kompany and Nasri, it's longer."