City make it three wins from three in Group C, then. Guardiola's team only need to pick up a point in the reverse fixture in Greece in three weeks' time to confirm their qualification for the round of 16. Olympiacos stay third, now three points behind Porto who beat Marseille 3-0 at home. Martins' team might need to focus on making it to the Europa League now.
Man City swat aside Olympiacos fairly easily to tighten their grip at the top of Group C. City were just too good for the visitors, who livened up briefly in the second half but never did enough to cause the hosts real problems.