That defeat to Auimatagi still rankles with Jackson.
"We are still learning in the pro game. It doesn't matter how many fights you have. I was disappointed on that loss but you can't win them all and I have learned from it and will try not to make that same mistake again.
"We just have to move on and look ahead instead of dwelling on the past. (Tonight) will be good for me being on the Parker card as it is good exposure because it is going to be televised in Aussie, America and Europe.
"It is definitely a huge card to be on. I am comfortable fighting at super middleweight. I am stronger, quicker and ready to go."
Jackson's trainer Chris Walker says Jackson has been sparring hard ahead of the bout.
"With Gunnar it is all about getting him up on the night and he seems to be up and right for this.
"If you look at the TAB they have him down as a big underdog to be quite fair, considering his opponent was knocked out in his last fight.
"They must think Gunnar is done and dusted but he is definitely not done and dusted and he is coming into this fight with a bit of intensity."
One of the other fighters in Walker's stable, Jonathan Taylor, was in the ring last weekend and had a comfortable victory over Kendall Cooper in a Super Middleweight bout.
"He went really well actually. He knocked the guy out in 36 seconds and Kendall is actually quite a durable sort of a guy who spars with the top guys in Auckland," Walker said.
"I had a good look at him and we had his number to be quite fair. Jonathan is quick and he punches very, very hard.
"I was pretty happy with that and he is fighting in Tauranga on October 15 at our show."