Swindon's second goal - scored by James Collins - in Tuesday's 2-0 win over the Glovers at Huish Park nudged Yeovil out of the play-off spots.
And ahead of the trip to Carlisle, the former Bristol City boss spoke of his confidence that their coaching staff can turn their fortunes around.
"I'm confident that me, Terry (Skiverton) and Darren (Way) will do all we can to get a response up at Carlisle," Johnson said. "We have got to make sure we are ready.
"We must not let our season fade away, I will not let that happen. We have to make sure in the next couple of games we fight back and get in those play-offs."
Johnson also confirmed that Jamaica Under-20s captain Omar Holness has left the club after a trial period.