The Brazil international's fourth strike in his last five European matches followed a surging run from Ross Barkley, who impressed in Thessaloniki.

Chelsea's winning margin should have been far wider, but they were wasteful in front of goal, with Alvaro Morata the main culprit.

But it mattered little as the Blues secured three points in what could be the toughest of their away trips in Group L.

Sarri's side quickly set about quietening the vociferous home support and within seven minutes Willian succeeded, his low shot somehow squirming under Alexandros Paschalakis' body.

Morata should have doubled Chelsea's lead soon after, but his problems in front of goal continued as he inexplicably headed wide from six yards.

The Spaniard wasted another five chances before the break as Chelsea failed to turn their domination into a healthy lead, Pedro also guilty of spurning a gilt-edged opportunity.

Marcos Alonso and Antonio Rudiger both failed to convert on the hour as Chelsea's control of proceedings continued, the latter unable to tap home from Barkley's front-post flick.

Even the introduction of last-season's top scorer Aleksandar Prijovic could not spark PAOK into action, the substitute having to live off scraps as the hosts struggled to make an impact.

Cesc Fabregas made a welcome return from a knee injury midway through the second half, while Morata's frustrating night ended with 10 minutes to play when he was replaced by Olivier Giroud.