Speaking to the official site, Leeds born Liddell was thankful to Rotherham for giving him the chance to return to league football.
"I would like to express my gratitude to the manager for giving me the opportunity to play", said Liddell.
"I got a call from John Breckin asking what I was upto and at the time was training at Bradford Park Avenue. I haven't done much pre-season due to family circumstances but I have really got the bit between my teeth.
"I am a bit behind the rest of the lads but the last few games have really helped me become fitter and stronger. The initial month could give me a chance to keep improving and hopefully I can be of use to the club."
Liddell spent the previous four years with Oldham, scoring 33 times.