Sources: Three Celtic players key to O'Neill keeping his job
Celtic chiefs are considering sacking Martin O'Neill if he is unable to get the best out of their big-money summer signings, sources have told Football Insider.
O'Neill's future at Parkhead is under scrutiny following a turbulent week for the club on the pitch.
Two defeats to arch-rivals Rangers with an aggregate score of 4-0, either side of a Europa League defeat to Ferencvaros, have seen many fans call for the 74-year-old to leave his role in charge.
CEO Michael Nicholson revealed in an official statement on Tuesday that the Hoops' board will stand by O'Neill for now.
As I revealed on the latest edition of Football Insider's Transfer Insider podcast, further struggles regarding their key summer signings will play a huge part in deciding his future at Parkhead.
The likes of Camilo Duran, Kasper Hogh and Haissem Hassan have impressed on occasion for Celtic but are each still yet to show their best form since joining in the summer window.
Martin O'Neill must change fortunes of key Celtic stars to keep his job
Celtic spent around £31.6million on O'Neill's squad over the summer after selling Arne Engels to West Ham for £22m.
It is clear that the Hoops boss is relying on his star men to rediscover the form that earned them moves to Parkhead as he looks to stay in charge.
Speaking on the Transfer Insider podcast, I explained: "Obviously, the Celtic chief executive has come out and backed Martin O'Neill, saying that everyone at the club is behind him to try and turn things around. They did spend a bit of money in the summer window with the new signings Kasper Hogh, Camilo Duran and Haissem Hassan.
"They brought in a number of players just before the deadline as well, who maybe, so far, have not been able to show what they can do. It was a disappointing week for Celtic, losing two Old Firm games and losing in Europe as well. It has piled the pressure on O'Neill and everyone there."
Celtic can afford Kieran McKenna payout if O'Neill decision is made
McKenna has been linked with the Celtic job once again in recent weeks, and was even spotted watching on at Parkhead for their 1-0 defeat to Rangers.
Former Aberdeen chief executive Keith Wyness has exclusively told Football Insider that McKenna's £8m compensation clause would not be a deterrent for Celtic if they wish to make him O'Neill's successor.
He left Ipswich Town in June after guiding them back to the Premier League, and they would be entitled to such a fee if another club wanted to appoint him within 12 months of his exit.