Pat Fenlon never regained the faith of the Hibernian supporters after losing 5-1 to city rivals Hearts in last year's Scottish Cup final, according to goalkeeper Ben Williams.
The 44-year-old Irishman resigned as Easter Road boss on Friday - just two days after fans protested outside the stadium following Hibernian's second derby defeat to the administration-hit Jambos this season.
But Williams believes Fenlon had been living on borrowed time with the club's followers ever since the dark day of May 19 2012, when the club suffered their Hampden humiliation against Paulo Sergio's Hearts.
Ahead of Sunday's Scottish Premiership trip to Motherwell, the 31-year-old Englishman told Press Association Sport: "The fans are entitled to their opinions. They pay good money to come and watch us, and without them the club is nothing.
"But it has been difficult for the manager with the fans ever since the cup final defeat to Hearts.
"This season, a couple of results against our local rivals - who are struggling - have magnified things.
"He recovered as a manger and turned things around but that 5-1 defeat has stuck long in the memory of the fans and their frustration was clear to see after Wednesday's loss."
Fenlon saved the club from relegation in his first season in Edinburgh but still ended up clinging on to his job following the cup final performance.
Last season was better as the former Shelbourne boss guided the Leith men to seventh in the Scottish Premiership as well as a second successive Scottish Cup final.
But they lost that game by three goals to Celtic before starting this campaign with a mortifying 9-0 aggregate capitulation to Malmo in the Europe League qualifiers.
Worse was to come as Hearts - docked 15 points for breaching insolvency rules and banned from signing new players - still managed to rack up a pair of derby victories, with the second coming in Wednesday night's League Cup quarter-final.
Fenlon walked after deciding he had taken the club as far as he could, leaving assistant boss Jimmy Nicholl in charge for Sunday's trip to Motherwell.
But Williams says the players must accept some of the blame.
Admitting he was stunned to see the boss quit, Williams said: "It came totally out of the blue.
"There was a lot of negativity after Wednesday's game but no-one expected the gaffer to be gone before Sunday's match.
"I couldn't believe it because while I've only been here about 15 months, I think the squad has improved massively.
"Since the manager came in, we've gone from a team battling against relegation to seventh place in the SPL and two cup final appearances. We're only five points off second place now.
"But football is an immediate, results-based business and people want fast results quickly no matter how realistic their expectations are.
"All the players are responsible because we are the ones on the pitch. The manager can only control so much. We should have beaten Hearts on Wednesday and perhaps it might have been a different story for the manager.
"There is an element of guilt definitely. If we had done better the manager might not have been under the negative scrutiny he has faced, which forced him into this decision."
Hibs captain James McPake is suspended at Motherwell but striker Paul Heffernan returns after being cup-tied and full-back Alan Maybury could come back after a thigh problem.
Motherwell goalkeeper Lee Hollis (ankle) remains on the sidelines while James McFadden could make his comeback from a hamstring injury.
Manager Stuart McCall is determined to bounce back from Motherwell's League Cup exit when they face Hibernian - but he admits he will never be able to forget their midweek defeat by Aberdeen.
Well looked a good bet to make the last four when Dons right-back Joe Shaughnessy was sent off after McCall's side had made a lively start to the Fir Park clash, but they could not break down a resolute 10 men and lost two late goals.
McCall said: "I've been very, very fortunate in my career to have lots of highs and great nights both as a player, coach and manager.
"I've got to say nights like the other night probably stay with you longer and deeper.
"I look back to losing the first-ever play-off with Bradford and not getting up to the Premiership, losing to England at Euro 96, not getting a second treble (with Rangers) in the cup final against Dundee United, not getting through against Arsenal in the semi-final of the FA Cup (with Sheffield United).
"I will never forget that night because it was an opportunity for us and as much as it's gone and we can't do anything about it, it will stick with me forever like a lot of sore defeats do."