St Johnstone took the lead but couldn’t take any points at Celtic Park.
A Dedryck Boyata own goal gave the visitors the perfect start.
But it was soon cancelled out by a Leigh Griffiths equaliser, and then Celtic took the game away from the Perth men with strikes from Tomas Rogic and Charlie Mulgrew.
Alan Mannus had an early save to make at his near post from a well-struck Emilio Izaguirre shot, but other than that, it was a comfortable start to the game for Saints.
And it was even more comfortable when the opening goal was scored on 11 minutes, Boyata finding his own net after Michael O’Halloran had hit the byeline and delivered a low cross into the danger area.
With pre-match protest banners unfurled by the Green Brigade saying “gutless in Malmo” and “clueless in boardroom”, and restless Celtic fans in every other corner of the stadium, it was a shame for the Perth men that they couldn’t crank up the pressure for longer than just seven minutes.
That was how long they managed to hold on to their lead.
Tam Scobbie cleared a Griffiths header off the line and then moments later the Celtic striker found the target when a long-range shot was deflected over Mannus for the equaliser.
There was a worrying clash of heads between Murray Davidson and Izaguirre but, after lengthy treatment, both men were able to continue. And, seconds after coming back on, the Celtic man nearly set up a second for the hosts with a cross to the back post. But Griffiths was narrowly wide with his header.
In the 45th minute Celtic took the lead when Rogic worked himself into space and gave Mannus no chance with a fierce shot.
Davidson didn’t reappear for the second half, and was replaced by Liam Craig.
Celtic had far more territorial dominance in the second half and they got their third on 67 minutes.
Mannus did brilliantly to tip a Kris Commons outside-of-the-boot shot past the post but from the subsequent corner Mulgrew headed home.
John Sutton was brought on for Steven MacLean and he made his presence felt first by setting up Graham Cummins, who couldn’t get a shot away, and then with a volley that grazed the top of the bar.
There was an injury-time Brian Easton free-kick well saved by Craig Gordon, and a brilliant double save from Joe Shaughnessy and O’Halloran, but it finished 3-1.