It's been 20 years since boxing has had an undisputed heavyweight champion, Lennox Lewis. Now that Tyson Fury has beaten Deontay Wilder to claim the WBC and lineal heavyweight championships, fans, promoters and fellow fighters are clamoring for a unification bout between Fury and Anthony Joshua, who holds the other three recognized heavyweight world championships (WBA, WBO and IBF).

You can add former champs to the list as well. We canvassed George Foreman, Evander Holyfield and 15 other former champions -- both heavyweights and luminaries from other weight classes -- to get their opinions on whether boxing needs one true champion in its glamour division.

The resounding answer from our blue-ribbon panel of former stars? Yes, boxing needs a Tyson Fury vs. Anthony Joshua bout.

Bernard Hopkins (career record: 55-8-2), held multiple world championships in two weight classes, including middleweight (2004-05) and lineal light heavyweight (2011-12): "The heavyweight division has been in a coma for so long. When is the last time we had an undisputed, recognized champion with all the belts? Fury-Joshua is the biggest fight that you can make in the heavyweight division right now. Both guys, they're in position to say, 'I'm the king of the heavyweight division.'"

George Foreman (76-5-0), Olympic gold medalist and two-time world heavyweight champion: "If you want to be considered the champion, you gotta come to Fury. Fury-Joshua would be like Barnum & Bailey Circus coming to town."

Evander Holyfield (44-10-2), only four-time world heavyweight champion: "Fury-Joshua would be the biggest fight in history, because Joshua is a two-time heavyweight champion of the world, which shows he knows how to recover from setbacks. Joshua may be the most talented out of all of them. He's got the credentials. Now can he get to that space of, 'I lost a fight, I came back, I beat the guy. How do I grow from this?' The winner of the Fury-Joshua fight would be the true heavyweight champion -- undisputed."

Riddick Bowe (43-1-0), first boxer -- and only heavyweight -- to win the titles of all four major sanctioning bodies (WBA, WBC, IBF and WBO): "Without question, I think that a Fury-Joshua fight would be tremendous. Joshua is so polished. He can box. Whoever shows up that day, that's who wins. Without question, that fighter will be the undisputed heavyweight champion."

"Sugar" Shane Mosley (49-10-1), held multiple world championships in three weight classes, including lightweight, welterweight and junior middleweight: "It should be inevitable that Fury fights Joshua, because Joshua is the world champion. It's going to be one of those big fights, like Tyson-Holyfield. And the winner of that fight can say that he's the champion of the world."

Andre Ward (32-0), unified WBA, IBF, WBO and Ring light heavyweight titleholder (2016-17): "I think it's imperative that Fury fights Joshua. There's pressure on Fury to look directly at Joshua, and then there will be more pressure on Joshua than there ever has been. And for us to finally get an undisputed champion ... I know Fury wants that, and I'm sure Joshua wants that as well."

Vinny "The Pazmanian Devil" Paz (50-10), IBF world lightweight champion (1987) and WBA junior middleweight champ (1991): "People want to see that fight. When people say [undisputed champion], my mind goes to Ali, Tyson. That's such a big moniker to put on somebody. The heavyweight division is stacked with some pretty good guys."

Micky Ward (38-13-0), held the WBU junior welterweight title in 2000: "When you have a great heavyweight division, boxing blossoms. If you don't have it, it doesn't. Heavyweight is where the people want to watch. Yeah, Fury would be recognized as the heavyweight champ, and rightfully so. I think he will be -- and should be -- the heavyweight champ of the world. Joshua is a great fighter, but until someone beats Fury, he is the champ."

Now that Tyson Fury has claimed the WBC and lineal heavyweight championships, will we see a unification bout between Fury and Anthony Joshua, who holds the other three recognized heavyweight world championships (WBA, WBO and IBF)? ESPN Illustration

Tim Bradley Jr. (33-2-1), held five world championships in two weight classes (junior welterweight and welterweight): "I think Wilder and Fury are the two best heavyweights in the world, even though they don't have all the belts. If Fury fought Joshua in England? Oh my gosh! It would be unreal. I don't think they have a stadium big enough for that. It would be the biggest fight in this era, and the winner will be mentioned amongst the best heavyweights of all time."

Michael Moorer (52-4-1), held the WBO light heavyweight (1988-91), WBO heavyweight (1992-93) and unified WBA, IBF and lineal heavyweight (1994) titles: "The heavyweight division is not like it used to be. I'm not saying that in a bad way. There were more competitive fighters back in my era than there are now. They need to get rid of the cruiserweight division and just have two heavyweight divisions: heavyweight and super heavyweight. Wilder and Fury should be fighting in super heavyweight [230 pounds and above]. True boxing fans want to see just one unified heavyweight champion of the world. Are we going to see that now? It's possible. But are Fury or Joshua the ones who can do it? I don't know."

Lamon Brewster (35-6-0), held WBO heavyweight title from 2004 to 2006: "At this point, the world wants to know: Who sits at the top of Mount Everest? I think it's a travesty if these guys aren't speaking each other's names immediately after this fight. Boxing owes it to the fighters and to the fans."

Kevin McBride (35-10-1), heavyweight who beat Mike Tyson in 2005 via a sixth-round TKO: "Fighting Joshua -- that'll be the moneymaker, you know? You want to beat the best. The world wants to see Fury and Joshua. Whoever wins that one will be the world heavyweight champion."

Joseph Parker (26-2-0), held the WBO heavyweight title from 2016 to 2018: "Fury should match up with Joshua. That is the ultimate fight. Then the winner can say, 'I was the unified champion.' The winner of that fight would go down in history and be remembered as the best of this era. That's why everyone is so excited; we are so close to seeing who that one person is."

Charles Martin (27-2-1), held the IBF heavyweight title from January to April of 2016: "The best should fight the best. But undisputed world champ? He can be all that and a bag of chips until he fights me."

Shannon Briggs (60-6-1), held world heavyweight lineal title from 1997 to 1998 and WBO title from 2006 to 2007: "Definitely, 100 percent, once the smoke clears, Fury has to fight Joshua. People are getting tired of having multiple heavyweight champs -- they want one dominant champ. But Joshua has a tough fight coming up against Kubrat Pulev. What will happen the next time Joshua gets cracked?"

Juan Manuel Marquez (56-7-1), held nine world championships, including featherweight, junior lightweight, lightweight and junior welterweight titles: "Fury vs. Joshua would be a great fight because both fighters are for England. Joshua is one of the best fighters in the heavyweight division right now. I think he can win a fight [against Fury]."

Chris Byrd (41-5-1), two-time world heavyweight champion: "It'd be a humongous fight. It'd be huge for the heavyweight division. Just fight. I don't believe in the Joshua stuff where you wait a few years, like, 'I'm not ready.' Bro, you a champion! Less talk, more action. Never tell the public, 'Let me wait a few fights to get mad.' Really? Once you win a world title, everything is out the window. You fight anybody."