While the majority of Kidney's troops have been released for Magners League action this weekend, Sexton stayed behind in Limerick, and Kidney insists his young star will have no problem lining up against South Africa on November 6.
"Jonathan is in a situation whereby all the outhalves need to know what's going on in terms of our own shape and things like that," Kidney said.
"In terms of the game time, I think he has had three, three-and-a-half games so if he's not ready for the November series after those, then he wouldn't be ready to go to the World Cup next year.
"Because if he goes to the World Cup then he'll have even less build-up, that's the risk leading into the World Cup.
"So what is the ideal amount for a guy to play? There's no sports science that has the answer to that.
"For me, maybe around three, four, five games is the optimum. But injuries will get in the way of that, selections will get in the way of that, for some guys form will come into it.
"It's so important that we work together at this time. If we don't work together on it, and we pick holes in it, then the thing is just going to fall down.
"We have an Irish situation and the solution to it over the last few years has gone pretty well, even though there have been calls for a debate on it. But we'll continue to work at it."