Hearts winger Gary Mackay-Steven knows they cannot afford to underestimate his former Celtic team-mates when they visit Tynecastle on Saturday night.
But Mackay-Steven is determined to impose Hearts' attacking game on their visitors as they return to the top flight.
Celtic crashed out of the Champions League against Danish side Midtjylland in midweek and a young defence shipped six goals to West Ham in a friendly days earlier.
Mackay-Steven said: "A lot has been said about Celtic but it's still Celtic, still a massive team, a massive challenge and they have still got great players.
"We know it's going to be a tough, tough game. I still know a lot of the boys there and the quality they have.
"We won't underestimate them at all. They are as tough a game as you'll get to start with.
"But at the same time we want to focus on ourselves, impose our style of play on the game and come out with a good performance and a good result."
Swedish centre-back Carl Starfelt is set to feature after his first Celtic training session but the inexperience of the Hoops back line could give Hearts an opportunity.
Former Aberdeen and Dundee United player Mackay-Steven said: "It's not just Celtic, we want to attack any team and show how good a team we are. But they play for Celtic, they are good players. They have had some mixed results but it's going to be a tough, tough game.
"But we go into every game confident, we are a big team and want to focus on ourselves attacking and creating chances.
"Last season proved different challenges. It's a tough league, the Championship, teams sometimes sit in, sometimes try and play.
"In this league, certainly Celtic like to impose our style, but we need to concentrate on ourselves and impose what we have been working on and bring the confidence. Especially when we are playing at home, we want to take it to each team that comes."
