Celtic full-back Alistair Johnston came off the bench to break Dundee's resistance with his second goal in four days in a 2-0 win at Parkhead.

Johnston netted the opener from close range on the hour mark, three minutes after being called into action, and Arne Engels scored from the spot seven minutes afterwards to keep the champions top of the Scottish Premiership with a 2-0 win.

Dundee goalkeeper Jon McCracken, who was back in for the injured Trevor Carson, made impressive saves at the start of each half but the visitors generally limited Celtic's clear-cut chances.

Celtic manager Brendan Rodgers made six changes but two of the players coming in were established defenders Greg Taylor and Cameron Carter-Vickers, who partnered Auston Trusty, while record-signing Engels returned amid the ongoing absence of Callum McGregor.

The much-changed league leaders struggled to create real chances in the first half, with only one Kyogo Furuhashi effort testing McCracken.

But the 55th-minute triple introduction of Johnston, Reo Hatate and Daizen Maeda sparked them into life, with Hyun-Jun Yang's low cross turned in by the former moments later.

That settled any nerves before a soft penalty gave Celtic the kind of cushion they would never give up. Kyogo took a tumble in the box under Antonio Portales' tug, and Engels stepped up from the spot to seal the hosts' victory.