Midfielder Osman had been struggling with a calf injury but is back in training while right-back Johnson suffered a knock to his ankle in the challenge which saw Stevenage defender Darius Charles dismissed a fortnight ago.
Manager Ian Sampson said: "Abdul and Johnno trained on Monday and Tuesday.
"They came through that okay without showing any adverse reaction so fingers crossed they should be okay for Sunday."
Midfielder Ryan Gilligan will make his 200th appearance for the club while striker Tadhg Purcell is recovering well from a knee injury and club physios are happy with the striker's progress as he battles to be fit before the end of the season.
Source: PA
Source: PA