The 32 year old has joined on an emergency loan and is in the team for tonights trip to Bristol Rovers, and explained his shock at the move to the clubs official website.
"I got a phone call last night from my gaffer, I was very surprised but when I asked who the club was and he explained I thought it was an opportunity to come and play football. That is what I am about, I don't believe in sitting on benches so I decided to take the opportunity to sign for Rotherham and I have got a big grin on my face, I am very pleased."
Despite being known as a bit of a hot-head in his previous term with the Millers, Guy admits that time has clamed him down; "I am a different person now, a lot more calmer and relaxed, and this is a different club, We have a new manager and new players, other than Warney, so it is going to be really enjoyable. I am a positive person so hopefully we can win a few football matches and go from there." he added.