English superstar Joshua is a healthy favourite to prevail when he meets New Zealand fighter Parker in their world heavyweight title unification bout in Cardiff on Easter Sunday (NZ time).
Many believe the WBA and IBF champion will be too powerful for the WBO belt holder from South Auckland, referencing the fact all 20 wins on Joshua's perfect professional record have come via knockout.
But respected UK boxing commentator and analyst Steve Bunce, a well-known voice in the sport, is one of an increasingly sizeable contingent who are giving Parker more chance than the odds would suggest.
Speaking on the latest 5 Live boxing podcast with longtime BBC boxing correspondent Mike Costello, Bunce said the 24-0 champion from New Zealand had an advantage in one crucial area.
"As a pro what he has done is get an awful lot of rounds. All three of his world title fights have gone the 12 rounds and he had done 12 rounds before that. And some of them weren't easy, he had to think.
"People in the Joshua camp, one of the biggest camps in world, would say that's because Joshua doesn't need to take the rounds, he's has bashed and smashed people up.
"I don't necessarily agree with that, sure he's bashed and smashed people up but without a doubt the better professional boxer right now, not the most explosive, not the most popular, but the better professional boxer, the better schooled, the guy who has got the better skillset looking at a 12 round fight is without a doubt Joseph Parker. Let's get that clear straight away."
Bunce bases his statements not only on what he has seen but also what the numbers and other facts show.
Parker has racked up 123 rounds during a professional career of less than six years, while Joshua has only 65 since his professional debut in 2013.
The 26-year-old Kiwi has also been boxing for much longer, having got his start in the sport at a young age, with the rapidly-rising Joshua not introduced to the sport until he was 18.
The Parker camp also have also indicated they believe their man will be the frontrunner if the fight goes the distance.
Joshua's stamina has been questioned on several occasions since negotiations for the bout began last year and a lean, mean-looking Parker is looking fitter than ever after a strict training camp at his Las Vegas base.
"When you look at Joseph Parker he is one of those fighters that doesn't do anything brilliantly but he does everything well, including taking a shot," Bunce said.
"He has got that history, he has got that solid amateur pedigree."
Another well known name in British boxing is also adamant people should not be writing Parker off.
Former heavyweight champion David Haye, who has a re-match with English counterpart Tony Bellew this weekend, told Bunce and Costello that the WBO champion is a real threat to Joshua.
Currently hosting the Parker team at the hotel in London where he lives and has a gym, Haye used Joshua's 11th-round knockout win over longtime champion Wladimir Klitschko last year to make his points.
A then 41-year-old Klitschko put Joshua on the canvas during the bout, but was unable to finish the job as the big Brit fought back for a famous victory.
"Klitschko is a very defensive fighter ... when he gets you hurt he doesn't jump on you," Haye said.
"That's very different when you have a young, hungry fighter in front of you. Klitschko had made the mistake before of being gassed out and being beaten.
"But Parker doesn't know how to lose, he hasn't lost as a professional. If he manages to wobble Joshua he's not going to stand off like Klitschko did, he is going to pile on the pressure and empty the tank.
"That is the difference in this fight ... as soon as one of the fighters shows any weakness the other fighter is going to jump all over him."