Chelsea midfielder Danny Drinkwater and winger Victor Moses "have to improve" if they want a future at the club, says manager Maurizio Sarri.
Drinkwater, 28, has played just once for the Blues this season, in the Community Shield, while Moses, 27, has made six appearances.
When asked if they still have Chelsea futures, Sarri said: "I don't know."
He added: "They have to improve, but the characteristics are a little bit different."
Moses was a regular under previous manager Antonio Conte, but of the Nigerian's six appearances this season only two have come in the Premier League and he has started just once.
Meanwhile, Drinkwater has only featured on 23 occasions since his £35m move from Leicester in September 2017.
"The situation is that Drinkwater for me is not suitable for a midfield with two midfielders," Sarri said.
"I told him two months ago what I think."
The England international is vying for a midfield place with N'Golo Kante and Cesc Fabregas, as well as summer arrivals Jorginho and Mateo Kovacic.
Conte employed a 3-4-3 system during his time at Stamford Bridge, utilising Moses and Marcos Alonso as his wing-backs, but with Sarri opting for a 4-2-3-1 formation, Moses has been unable to break into the team.
"Moses is more suitable for playing like a wing-back than like a winger or a full-back," Sarri added.
Only Wolves have used fewer players than Chelsea in the Premier League so far this season.
However, Sarri did admit there could be more opportunities for squad rotation as the Premier League enters its busy Christmas period.
"Of course if you look to December, January - we'll need to change [the team] for the Premier League because there will be matches every three days," he said.
"So we'll need to change there too, of course."