An eight-point chasm was about to be opened up between them and third-placed Raith Rovers at the top of the SPFL Championship. But then Dougie Hill, the Raith defender, picked up a second yellow card.
His challenge was late - a crude tackle on James Keatings on the touchline - and it resulted in the 10 visitors discovering a steely resolve, thwarting their hosts, stifling Hamilton's creativity and thumping courageously into meaty challenges.
For all their pluck and endeavour, though, it was a contentious call that sent Raith along the path to parity. Substitute Gordon Smith was adjudged to have been brought down in the box by Michael Devlin, much to the chagrin of the home players. Calum Elliot duly converted.
"The referee has gifted them a way back into the game with an unbelievable decision," said Alex Neil, the hosts' manager. "It's not a penalty."
Hamilton had taken an early lead. Ali Crawford sent a perfectly weighted ball through to the rushing Keatings. Sometimes an offside trap is subtle, snapping tight on wayward strikers. Here, there was simply a vast expanse of space to exploit; Keatings finished cooly past David McGurn. "It was an eventful game," laughed the goalkeeper afterwards. "The boys are happy, the gaffer's delighted. It was a magnificent point for us."
McGurn had played a crucial role. Though strangely untroubled in the second half, as Hamilton huffed and puffed, his glory was already won. It was just before half time; Raith were hanging on, wildly trying to reach the interval to regroup. Darian McKinnon struck a sweet volley, tremendously saved by the diving hero.
It meant a buoyant Raith emerged from the tunnel only one goal down. And as the home side spluttered, the visitors dug in and pinched a point. "Being a Hamilton supporter," said Neil, "you'll feel like it's a defeat today. We were a bit naive at times and it came back to haunt us."