Paul Lambert on Martin O'Neill's Future at Celtic

Paul Lambert says he would not be surprised if Martin O'Neill chose to walk away from Celtic – but he cannot imagine the club sacking the manager who has defined an era.

O'Neill, now 74, has been left reeling by a bruising run of results. Celtic have lost back-to-back Old Firm derbies to Rangers, either side of a home defeat to Ferencvaros in the Europa League. That sequence followed a stunning Champions League collapse against LASK in August, when a 4-0 aggregate lead was thrown away.

The manager has already signalled that the international break will be used to take stock.

"I will reflect on the games," said O'Neill, who was made permanent manager for a second time in the summer after two spells as interim boss last season ended with a league and Scottish Cup double.

He knows exactly where the responsibility lies.

"I'm not immune from criticism. Absolutely and utterly far from it," he said. "I think there's every reason to ask 'can you turn this round? Can you change the whole thing?' I have to kind of look at the bigger picture at this minute."

For Lambert, that bigger picture still paints O'Neill as a giant of the club.

The former Celtic captain, who lifted trophies under O'Neill between 2000 and 2005, calls him the club's best manager since the legendary Jock Stein. Yet Lambert accepts that O'Neill may decide he has had enough.

"It wouldn't surprise me if he left. I don't think he needs it," said the 57-year-old.

What Lambert cannot accept is the idea of Celtic pushing him out the door.

"I'd be shocked and disappointed if Celtic sacked him," he said. "I think they give him the option, if that's what's on his mind, if he did want to walk away.

"He's got enough credit in the bank. It wasn't that long ago people were shouting for a statue for him, so I don't think you can go from one extreme to the other.

"If he wants to go, then he goes himself."