The Greek forward drilled home in the 34th minute following a Kris Commons through-ball and Celtic comfortably saw out the win even if their performance failed to match the spark of their maiden Champions League away victory against Spartak Moscow.
On Saturday, Hibernian had briefly moved top of the table with a 3-0 win over basement side Dundee. Eoin Doyle, Leigh Griffiths and David Wotherspoon got the goals.
Elsewhere Aberdeen won 3-1 away at Kilmarnock. The Dons now sit third, with Killie sat sixth. Ryan O’Leary gave the home side the lead on three minutes, but Gavin Rae, Niall McGinn and Scott Vernon hit back to give the visitors the three points.
St Johnstone extended their winning run, defeating St Mirren 2-1, with Nigel Hasselbaink and Murray Davidson firing goals in the first half. Lewis Guy scored for the visitors.