"I have been training with Lolo Heimuli out of City Boxing. It has been a lot different and almost like a breath of fresh air. It has all been about what I do and what I can bring to the table. I haven't really looked at what he does and how to stop him. I will just do what I do best."
Not surprisingly, Gallen believes his superior experience will be a key factor in beating Thompson tonight.
"It will be important knowing that I have been there and done it before. That experience will hopefully be able to shine through. But we have just finished a football season so are coming off a month's preparation," Gallen said.
"He is going to be tough, there is no doubt about that, and from what I have heard he is very, very fit as well. Going the four rounds is probably not going to be an issue for him."
Thompson admits to disappointment at missing selection for the Kiwis tour to England. He will use yesterday's loss to England in the first test as further motivation against Gallen tonight.
"It is something that will bring out a little bit of inner fire. I would love to have been there but you can't control what happens there. But when I found out about [non-selection], I knew I was going to fight so was extremely happy about that."
Thompson and Gallen have played against each other many times in the NRL but they both say there has never been any biff or niggle between them.
That will change big time later tonight.