Chelsea assistant Gianfranco Zola says defender Gary Cahill is right to be “upset” but must be patient in his bid for first-team football.

Last week, 32-year-old Cahill conceded he may have to quit Chelsea in January after dropping down the pecking order under Maurizio Sarri.

The England international came off the bench in the goalless draw at West Ham on Sunday, in what was his first appearance of the season in any competition.

With England reaching the World Cup semi-finals over the summer, Zola claimed Cahill’s late arrival back to pre-season means the centre-back has had less time to impress, though he could be in line for a first start at Liverpool on Wednesday in the Carabao Cup – live on Sky Sports.

“It is totally understandable that Gary is upset and we want him to be upset. It means that he cares,” Zola said.

“But he has been a top professional. He has been doing everything correctly and he just needs to be patient because he came late and there were players here that did very well.

“He will have his chances and then it is down to him to take those chances in the best way.”

Zola confirmed Wednesday’s trip to Anfield will likely come too soon for Pedro, Ruben Loftus-Cheek and Antonio Rudiger, while he was coy on how much Eden Hazard would feature as they also prepare to welcome Liverpool to Stamford Bridge in the league on Saturday.

However, Zola admitted the midweek Carabao Cup affair was a chance to give Cahill and Andres Christiansen a run-out, so too 17-year-old Callum Hudson-Odoi and 18-year-old Ethan Ampadu, described by the Chelsea legend as the “future of this club”.

Zola added: “Callum has done extremely well this pre-season. He’s one of the players that has probably impressed the most, along with Ethan Ampadu.

“They both have a bright future here. They are both in contention for tomorrow. They are in the squad and we will see.

“We have a lot of players. We didn’t do a big pre-season, so these games can also serve as a pre-season to give time for players like Christensen, Cahill, that didn’t have this opportunity to get games.

“Callum and Ethan are the future of this club, and we are going to take care of them. [Callum] is in a very competitive team with a lot of players, he has to be patient and take these opportunities when they come.”