Radoslaw Cierzniak was chief among them, the Dundee United goalkeeper denuded of his usual composure by Hearts' aerial approach but, to varying degrees, Nadir Ciftci, Jamie Hamill and the respective managers each let themselves become infected by the fiery atmosphere at a seething Tynecastle.
The feeling in the Hearts camp was that they had been denied victory by an unjust decision, referee Steven McLean and assistant Francis Andrews conferring before disallowing Dylan McGowan's effort after Cierzniak spilled a long throw apparently under duress from Jason Holt. They were vexed, too, by the perceived leniency shown towards Ciftci for a series of niggly fouls. United, meanwhile, protested about the robust approach of their hosts.
Hamill stated his intentions with a challenge designed to upbraid Ryan Gauld over any pretensions about Real Madrid's reported interest and set a snarling template for his callow colleagues to follow. That he and Ciftci had to be separated after the final whistle by an unlikely peacemaker, Hearts assistant Billy Brown, was a fitting epitaph.
United boss Jackie McNamara described the contest archly as "everything we expected it to be", having anticipated the Tynecastle side would focus on discomfiting a defence shown to be susceptible to physical opponents, but the United manager only grudgingly derived satisfaction from not conceding. Given how panicked his players looked when a ball was speared high into the area, he should perhaps have been more grateful.
Cierzniak had already desperately diverted a teasing David Smith free-kick away and watched Danny Wilson head a Kevin McHattie corner over before the incident that caused Hearts such despair.
The goalkeeper was caught underneath a long Callum Paterson throw into the six-yard box and, though he touched the ball, it spilled into the path of McGowan, who rammed into the net. Goal? Apparently not. Assistant referee Andrews flagged, with McNamara suggesting Holt nudged Cierzniak before the throw and again when the ball was in flight. Hearts manager Gary Locke disagreed. "I've seen it on the laptop and it's a goal," he said. "It's another sore one to take, but there is nothing we can do about it."
Hearts' ire was heightened by their failure to exploit United's shakiness. Cierzniak gathered efforts from distance by Holt and Smith and flung himself through the air to spectacularly thwart Hamill's rasping 25-yard scud.
The goalkeeper, though, was still not settled - he was bailed out by his defence after waving at another couple of crosses and made hard work of stopping a Jamie Walker drive - but the hosts lost a little of their intensity in the final half hour as the fatigue of playing 120 minutes in midweek began to tell. Consequently, United's defensive discombobulation was not tested further and McNamara's side instead showcased their attacking prowess. The trio of Ciftci, Gauld and Stuart Armstrong interchanged intelligently and embroidered little triangles of play in the final third. At times, it was too intricate, but when it worked, it was a delight.
Jamie MacDonald was alert to deny Keith Watson, John Rankin twice and Ciftci, after clever moves; Armstrong twice skidded wide; David Goodwillie found the side net and headed past an upright; and Ciftci's composed finish from Paul Paton's cross was disallowed after Goodwillie was deemed to have impeded Wilson.
Ciftci, especially, began to exert his influence, coming closest to establishing an advantage when he met Armstrong's cross, only for a combination of Hamill and the upright to divert clear.
Then the Turk bamboozled McHattie at the corner flag only to watch his cross bisect Goodwillie and substitute Gary Mackay-Steven. Goodwillie had a further chance, lashing wide, but United were left to muse on what might have been. "I thought it was there for us," said McNamara. "But our decision-making was poor at times in the final third."
Hearts would suggest they were not the only ones.