"He's in a lot better shape than he has been for other fights. He seems confident... I believe we'll see the best Andy on December 10."
Parker and Barry and preparing on the assumption the fight for the vacant WBO title will go the full 12 rounds. Barry, who took David Tua to a world title fight against Lennox Lewis in Las Vegas in 2000, which the Kiwi-Samoan lost, expects it to be one of the best of the year given the quality and styles of the two fighters.
"This could easily be a 12-round contest. Both guys throw a lot of punches. Game plans and how they are followed in this fight are going to be very important. Joe and I have a very good game plan, it's just a matter whether we can excecute it or whether Andy lets us.
"The style of this fight on paper is going to be a terrifically exciting fight. In fact, this fight could be the best heavyweight fight in the world this year, and I don't say that lightly. I've watched every fight I can, all the [top] heavyweight fights this year.
Barry said the 12-round battle against Carlos Takam in Manukau in May would stand Parker in good stead for a fight which he said was a far bigger challenge.
"It was great that Joe was able to experience such a war against Takam; to go to some dark places, because I expect us to go to dark places in this fight. This is going to go down to who wants it the most.
"You saw that fight - it was a life or death fight," Barry said. "Well let me tell you this - Andy Ruiz is a much bigger, far more dangerous challenge than Carlos Takam and it's going to take everything that Joe has learned in the last three and a half years... every bit of strength and desire in his body if we are going to win this fight. This is a very, very big challenge."