Brendan Rodgers has Celtic 'food for thought' as John Hartson reveals the squad unknowns key to transition

Brendan Rodgers will have 'food for thought' ahead of the new season at Celtic warns John Hartson.

The Welsh forward reckons the Irishman, who capped off his Hoops pre-season return with a 3-2 win over slick La Liga side Athletic Bilbao in James Forrest's testimonial, may look to tinker the tried and tested ways of former boss Ange Postecoglou who brought a domestic Treble to Glasgow. Rodgers, however, achieved a clean sweep of seven trophies from seven in his first spell in Glasgow and will lead Celtic to the Champions League group stage this season.

Five new faces have been recruited at Parkhead but a stalwart under Postecoglou in Jota has left, and Hartson believes the formation dilemma will be the beginning of Rodgers' transition back in to the Celtic hot-seat. A change that the former Arsenal man doesn't think will be as 'simple' as stated and that the 50-year-old must get to know his top stars before big games come around.

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He told Go Radio: "Brendan will have a lot of food for thought, when he was at the club the first time he had Moussa Dembele, Scott Brown and a different team, a different make-up of a squad. He was quite successful but now he doesn't really know the players too well. He'll know Callum McGregor, he won't know Kyogo, Maeda or Abada.

"He will have tried to get to know them as best he can in pre-season, but what system is he going to play? Brendan is a very clever football man and he knows different systems, the game and his philosophy of it. He will have food for thought. Ange was a 4-3-2 reluctant to never ever change from that. The fullbacks making six across the middle, Abada wide, Jota wide and