He delivered a double few thought possible last season when the Scottish Premiership and Scottish Cup were salvaged from the potential wreckage of one of Celtic's most tumultuous seasons.

He very nearly lifted the Uefa Cup in 2003 against a Jose Mourinho-inspired Porto who, the following season, won the Champions League.

His status as one of the club's all-time great managers is surely secure.

Which is perhaps why, so soon after returning to the club as its unlikely saviour, manager Martin O'Neill wondered out loud whether now, at the age of 74, it's finally time "to wrap it up".

The Northern Irishman's words came in the post-match news conference following a second defeat in a week against arch-rivals Rangers.

The fact he also joked about being "110 years old in two years' time" ought not to deflect from the fact O'Neill might now be seriously considering whether he's still the right man to be in charge of Celtic.

After such a damaging week, with a home European defeat to Ferencvaros in-between the two losses to Rangers, might O'Neill decide to protect his fine legacy at the club by walking away while the side is still top of the Premiership?

"I genuinely will reflect and see," he said. "It's a matter of whether I can help the team. The manager is supposed to be able to do that. I will look at that this week.