Martin O'Neill will walk into Celtic Park on Thursday night knowing the questions are coming before a ball is kicked.
A 3-0 derby defeat to Rangers in a League Cup quarter-final does that to any Celtic manager. At this club, one bad result does not just sting – it spirals. The noise grows, the scrutiny sharpens, and every team sheet becomes a referendum on the manager’s judgment.
Cillian Sheridan did not bother sugar-coating it.
Speaking on the BBC's Scottish Football Podcast, the former Celtic striker cut straight to the point: too many of O'Neill’s players simply vanished at Ibrox.
"There were too many players that didn't show up against Rangers," he said, laying the responsibility squarely on both the squad and the man who picked it.
Tounekti over Hassan – the call that jarred
For Sheridan, one decision leapt off the page when the teams were announced: Sebastian Tounekti starting ahead of Haissem Hassan on the wing.
He was "shocked" to see Tounekti get the nod, with Hassan – a summer signing expected to add spark and incision in exactly these high-stakes games – left on the bench until half-time in a tie that was already slipping away.
Sheridan felt the occasion, the intensity, the need for a front line that could punch back, all pointed towards a different trio.
"I thought the game was built for Hassan," he said, adding that he had pictured a front three of Hassan, Kasper Hogh and Camilo Duran leading the line from the start.
If there were concerns over Hassan’s fitness, Sheridan argued, that should not have been decisive. Start him. Let him empty the tank. Give him an hour.
"If there were worries over Hassan's fitness, you start him and give him 60 minutes," he insisted, admitting he "just knew" the half-time change was coming the moment the line-up dropped.
He was right. Hassan came on at the interval, but by then Rangers were in control and Celtic were chasing shadows in a quarter-final that drifted away from them with alarming ease.
Selection heat and a rapid response test
O'Neill, Sheridan believes, will not escape criticism. Nor should he expect to.
"O'Neill will maybe take a little bit of criticism, probably for his selections and one or two subs he made," Sheridan said, acknowledging the reality of life in the Old Firm goldfish bowl.
At Celtic and Rangers, there is no such thing as a quiet setback. A single heavy defeat can be framed as a crisis. A misjudged line-up becomes a talking point for days. Every substitution is dissected.
Sheridan fully expects the Celtic manager to react.
He can "imagine personnel changing" for Thursday’s Europa League opener at home to Ferencvaros, a match that now carries more emotional weight than a typical group-stage curtain-raiser. It is not just about European points; it is about restoring authority, about proving that Ibrox was a jolt rather than the start of a slide.
There is no gentle runway, either. Three days after Ferencvaros, Rangers await again in the Scottish Premiership. Same rival. Same questions. Same pressure.
One derby defeat has already turned up the volume. What O'Neill does with his next team sheet will tell Celtic supporters plenty about how he plans to turn it back down.
