Olivier Ntcham scored a 95th minute winner as Celtic recorded the double over Lazio and qualified for the knockout stages of the Europa League.
Lazio striker Ciro Immobile fired the home side ahead in the seventh minute when he was left unmarked to volley home.
James Forrest smashed a rising, angled strike across the goalkeeper and into the far corner to equalise in the 38th minute.
Ntcham scored the winner in injury time.
