Celtic manager Ange Postecoglou has warned his players they cannot assume they will have it any easier against Hearts despite making clear progress since losing at Tynecastle.

Postecoglou's side get a swift chance to avenge their opening league defeat when they host Hearts in the Premier Sports Cup on Sunday.

Celtic have since scored 13 goals in three victories after opening Postecoglou's reign with a Champions League exit at the hands of Midtjylland and a late defeat in Gorgie.

Kyogo Furuhashi has netted four times since making his debut off the bench at Tynecastle while Carl Starfelt has had more game time since his shaky beginning against the Jambos.

Celtic have also added Joe Hart, who almost brought the house down with a double stop in Thursday's 3-0 Europa League win over Jablonec, while Tom Rogic has been reintroduced to the Celtic midfield to excellent effect after some pre-season fitness issues.

Postecoglou agreed that his team were "definitely" stronger ahead of the second-round clash but Hearts will travel to Glasgow on the back of six wins from six this season.

"In the first game against Hearts I thought we were really competitive, we controlled it for large parts really well and they kind of nullified our threats a little bit," the former Australia head coach said.

"But we have made some progress since then and playing at home is an opportunity to make an impact in the competition.

"I remember that day, Carl had only had one session, Kyogo met us at the hotel and a couple of the other boys hadn't played pre-season.

"We are a bit further down the track, our football is improving a little bit but that's not to say it's going to be an easier game for us or one we will naturally dominate.

"We have got to work hard, Hearts are a good side, and it will be a good challenge for us."

Postecoglou added: "Cup games are always different, they always have a little bit of an edge because you know it's knockout and on the day the tie gets decided. It's exciting, we are looking forward to it."