Sometimes the negative can prove a positive. With nine minutes remaining, David Moyes summoned a substitute. The No. 7 was keyed into the fourth official's machine, along with the No. 5. Off went Nikica Jelavic, supposedly Everton's out-and-out goalscorer. On came Johnny Heitinga, whose endeavours in the centre of defence last season earned him the club's Player of the Year award.
Moyes was shutting up shop, settling for a replay. Everyone would reconvene at Goodison Park next month. Or so it seemed to a section of their supporters, anyhow. The jeers at the change became cheers after 89 minutes, however. Magaye Gueye's corner caused confusion, Marouane Fellaini an imposing penalty presence in the penalty box, and Heitinga's controlled shot flew past Andy Lonergan.
It was quite a way to mark Moyes' 500th game in charge. There was method to his seeming madness. "We needed to try and find another tactical way of trying to create a goal or score a goal," Moyes explained afterwards. He did so with a switch that was emblematic of his era. "We didn't have many options," said a manager who has rarely enjoyed a surfeit of them. "We played Fellaini a bit deeper and for the last 15-20 minutes I thought it might be worth pushing him a bit further forward." So Heitinga reprised the role in midfield he occupied in his younger days, a previously quiet Fellaini exerted a greater influence and Everton found a way to win the game.
And so they go marching into the last 16, the quest for the elusive first trophy of the manager's long reign gathering pace. The FA Cup almost brought the high point of Moyes' reign - Everton led after 25 seconds of the 2009 final - but it has also brought crushing lows, defeats to lower league opposition in Shrewsbury and Oldham the greatest embarrassments.
"The job is to get through in the FA Cup and I have had many years where I have not got through in quite similar games." On this occasion, their progress was threatened by a Bolton side who put their struggles in the Championship to one side and resembled the Premier League team that, until last May, they were, along with a familiar problem.
Kevin Mirallas' games have become a series of cameos. The Belgian has not reappeared after half-time in any of his last four starts and, beginning a game for the first time in seven weeks, his fragile hamstrings threatened to give way again. While Everton scored a minute after his removal, the absolute control they had enjoyed when he was on the pitch departed with the winger.
"You could see how well he played and how well the team played in the first 15 minutes," Moyes said. "We missed him after that." No sooner had he gone, however, than they struck in fortunate fashion. Victor Anichebe's shot took a sizeable deflection off the unwitting Steven Pienaar to defeat Lonergan.
If that seemed to herald serene progress, Bolton had other ideas. Marvin Sordell made a well-timed run to the near post to meet Darren Pratley's low cross and finished calmly. It was his fourth goal in three FA Cup games against top-flight opposition, form he has failed to replicate in the Championship. Indeed, when Sordell has made headlines this season, it has been for his apparent addiction to social networking sites.
Rather than being on the net, Sordell found it, clinically. "I'm so pleased for Marvin," manager Dougie Freedman said. "The leveller was "the way I want to play, I want to play football, I want to create opportunities that way. We worked on it during the week and it was great to see it coming off."
A further boost for Bolton came in the closing stages, Stuart Holden emerging to make his first appearance on home turf for 22 months. It could have been delayed still further; groundstaff had worked through the night to get the game on, aided by volunteers, and the outcome, Freedman felt, was "a kick in the teeth."
Others were at greater risk of drowning than dental damage. With water pouring off the roof of the West Stand on to the corner of the pitch, the Reebok Stadium had its own version of Niagara Falls, albeit with a snowy Pennine backdrop. Freedman, however, detected rays of sunshine for Bolton after a troubled 21 months. "You can see there is light there," he said. But this was a game illuminated by a surprising substitute.
MAN OF THE MATCH: Marcos Alonso. Fiorentina have bid for the marauding Bolton left-back and he illustrated why with a fine display. Breaking forward at will, he twice came close to goals with well-struck shots.
BOLTON VERDICT: Freedman felt it was the best Bolton have played in his three-month reign and it was a performance to suggest they should not be 16th in the Championship. In Chung-Yong Lee and Chris Eagles, they have attacking players with talent but this has become a season of transition.
EVERTON VERDICT: The opening 15 minutes illustrated the difference Mirallas makes. He was terrific and the good news for Everton is that Moyes felt his injury was "not too bad". Both replacements made a mark with Gueye hitting the bar in stoppage time. Otherwise, it was an unexceptional performance but a day when the result mattered more.
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