The full-back has not featured since playing against Crewe in April due to knee surgery but he then turned his ankle when he returned to full training and Johnson struggled to believe just what bad fortune the former Peterborough man has suffered.
"He hasn't had a setback on his knee," he explained to the Western Gazette. "He had just started training full-time and went over on his ankle. If you see him, cross over to the other side of the street.
"If a bomb drops anywhere near us don't stand next to Nathan Ralph as it's bound to fall right next to him. The poor kid has just had an unbelievable amount of injuries and operation after operation.
"We really are keeping our fingers crossed that he will come through and we're giving him every chance to get his career back on track."