Martin O'Neill has admitted he is considering his future as Celtic manager after their third successive defeat.
The Scottish champions were beaten by Old Firm rivals Rangers for the second time in a week on Sunday.
Ryan Naderi's first half strike clinched a 1-0 victory at Celtic Park to end the Hoops' perfect start to the new Scottish Premiership season.
It followed a 3-0 win at Ibrox in the Scottish League Cup last weekend.
Meanwhile, O'Neill's side suffered a reverse at home against Ferencvaros in the Europa League on Thursday night.
Celtic have now lost four matches in all competitions this season, as many as they did in 35 games under O'Neill last term.
O'Neill on his Celtic future
The 74-year-old was handed a one-year deal in June after guiding Celtic to a league and Scottish Cup double.
It followed his return for a second spell as caretaker manager in January of this year.
His time in permanent charge could soon be over, though, with O'Neill telling reporters: âÂÂI'm not immune from criticism. Far from it.
"Absolutely. They [fans] have every reason to ask, can you turn this round? Can you change the whole thing?
"It's not the first time I've been questioned about my managerial time. So, I'll have a look at it. I will reflect and see.
"Asking what I, myself, [can do], is the main thing. Asking what I can do to help the team. That would be the most important thing for me to see.
"I genuinely will reflect and see. It's a matter of whether I can help the team. If that's the case.
"The managerâÂÂs supposed to be able to do that and I will have a look at that there this week.
"That every single time that something crops up, things don't go so well, age plays a part. And you know what? They may well be right.
"I'm 110 in two years' time, so that might be a time to wrap it up. Listen, we've lost some big games. There's no question about it.
"I personally think every game here is big. We lost a European game. We lost the big match out in LASK and, here, two defeats against us. Of course you have to question it.
"I will reflect on the games. I'll obviously speak to the board. And, you never know, they may want to speak to me, but I'll see.
"I've got some time to do that there. I will try and get a couple of days away and see how it goes."
O'Neill previously spent five years in charge of the club between 2000 and 2005.
During that time, he won seven trophies including three league titles and reached a UEFA Cup final.
When do Celtic play next?
Celtic do not return to action for three weeks due to the first international break of the season.
Their next match will see them travel to face Motherwell on October 11.
As well as their latest run of losses, O'Neill's side were also dumped out of the Champions League last month.
Celtic were beaten 5-4 on aggregate by LASK in the play-off round.
Despite winning the first leg 3-0 at Celtic Park, they were unable to advance to the league phase.
Instead, Celtic suffered a 5-1 defeat after extra time in Austria, causing them to drop into the Europa League.