McCall revealed another two unnamed players were likely to be added to an injury list that already numbers five and includes the likes of James McFadden, ahead of Tuesday night's Highland clash.
But he has urged his fit players to double their efforts and get the three points that will take them into second place in the Scottish Premiership as they fight for a sixth season in Europe in seven years.
McCall said: "We are all going to be on a beach in six weeks, some might go to Rio, some might go to Largs, so now is the time to put our foot down and not think we're tired. We have really got to put everything into this.
"It might be in six weeks' time, lying wherever we are lying, that we look back and think 'it was a cold, damp, bobbly-pitch night up at Inverness that got us where we wanted to be'. That's how we have got to approach it.
"We have got to be really focused and positive and look to come back down the road back in second place."
The Tulloch Caledonian Stadium pitch might not be totally dissimilar to Largs beach, as Caley Thistle striker Billy McKay found out when the ball took a major bobble on the dry surface when he was clean through during his side's 2-2 draw with St Mirren on Saturday.
And those conditions will inform McCall's thinking as he sets up his tactics.
"You look at the games early season, the majority of teams will look to get the ball out from the back and pass it and build through," he said.
"You are actually taking a risk sometimes now in trying to do that because pitches can be drying out and a little bit bumpy.
"So you have got to play in the right areas, you would be naive to think you won't come a cropper sometimes passing it out from the back on some of the pitches we are playing on."
McCall has noticed Inverness playing out from the back more often under John Hughes than predecessor Terry Butcher, including during their recent 2-0 defeat at Fir Park.
"They had a lot of good possession, certainly second half, but we scored two really good goals," he said.
"I watched them last week up at Tannadice and they were certainly unfortunate not to take anything. They are playing a good brand of football and passing it well.
"The second goal highlighted that on Saturday, a 12-pass move. They are a bit like us at the minute - they have played a lot of games and have a few injuries but we are both in there fighting."