The 24-year-old bad boy, who has a lengthy rap sheet both on and off the pitch, has joined up with the Millers this week as he looks to find a new club following his release from Blackpool.
The Millers are in desperate need for reinforcements in attack as their time in the Championship looks like ending with a whimper, but Warnock says Ranger is only at the club to build fitness.
"Someone just asked me could have in for a few days and I never say no to a pro," he said. "He's had his problems everywhere, hasn't he. But I have never said no.
"He's a couple of
weeks away, so he will not be involved. But if he wants to train with us, it is
not costing us anything. If I can help him in any way, I will do.
"I have never
considered anything playing (contract) side. But like everything else, when you
see him through the gatepost, it's publicity isn't it.
"But he won't be involved
for a few weeks with us as he isn't fit enough."
