Assistant boss Darren Taylor stepped into the role at Alloa and helped the team to victory with the gaffer keeping his distance in the dug-out for fear of spreading his condition.
The same scenario could be replayed at Westfield on Saturday, although the manager is on the mend.
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He’s still had input on the team though with Falkirk training over the blank weekend caused by Ross County’s Irn-Bru Cup semi-final.
But he handed media duties over to Taylor again this week.
He said: “He’s been here in spirit all the time.”
Taylor took training and added: “The manager has never really been away. He did take a couple of days off at the tail end of last week but everything was organised and ready.
“We weren’t working towards a game - that would have frustrated him a lot. So in a way the timing helped. He has just used that time away to recover a bit.
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“The situation has had no impact at all on the team and we communicated regularly.
“I’m sure he will be in the dugout on Saturday – there’s no reason for him not to be. Like Alloa we have a big technical area so if he needs to keep a distance he can.”
The illness and role switch did not upset the Bairns momentum at Alloa with Taylor steering the side to a vital win, as McKinnon watched on.
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And while the management duo’s former club pose a strong threat, after a January full of transfers, Taylor is still confident.
He added: “Since 2019 we are on an unbeaten run and we intend to remain that way although it is a tough task. But we are happy to go toe-to-toe with them.”
The Bairns are at full strength. Zak Rudden will be available for the Bairns as the cautions he has accumulated have been spread out enough to avoid a suspension, for now.
William Edjenguele will not be available against his parent club though, as per his loan agreement.