St Mirren goalkeeper Craig Samson felt entirely justified in racing over to Iain Vigurs as the Inverness Caley Thistle midfielder remonstrated furiously with floored Saints team-mate Stephen McGinn.

Home midfielder Vigurs earned a second yellow card after the angry flashpoint in a vital victory for the title-chasing Buddies.

Samson, in contrast, received only a booking for what, from the main stand, looked like a highly provocative and aggressive act - and one which sparked a huge melee between opposing players.

In the eye of the storm stood referee John McKendrick, complicit in a number of controversial moments including the pivotal penalty award for Saints early in the second half.

But Samson argued he had only been protecting his younger teammate from the home player’s verbal assault. “It wasn’t a red card [offence],” said the 33-year-old goalkeeper. “I held him. It might have been harsh to send Vigurs off but he can’t be shouting in the boy’s face when he’s on the ground.”

In terrible wet, icy conditions, Caley racked up eight missed - or saved - chances in the first period and were then undone by a penalty that infuriated their manager.

Magennis managed to leave Gary Warren for dead on the left, before cutting inside the bye-line where the Saints attacker was challenged by Polworth. McKendrick pointed to the spot and Ian McShane sent Mark Ridgers the wrong way. Gavin Reilly scored later on to put the result beyond doubt.