Heavyweight kickboxing is back with the biggest event so far this year when the K-1 World Grand Prix 2010 in Yokohama takes place on Saturday. The event will air live starting at 4 AM ET on HDNet in North America, and Michael Schiavello, the announcer who will be calling the English-language broadcast both on HDNet and elsewhere around the world, joined me for a discussion about the five biggest fights on the card. Our discussion, which touches on Alistair Overeem, Semmy Schilt, Badr Hari and more, is below. 1. Alistair Overeem has said he'll turn his focus back to MMA, defending his Strikeforce heavyweight title against Brett Rogers on May 15 and then, he hopes, taking on Fedor Emelianenko. Is Saturday's fight against Dzevad Poturak the last we'll see of Alistair Overeem in K-1? Michael Schiavello: Definitely not. Alistair is too highly paid by K-1 to never fight in the promotion again and has had too much success in a short time to give up aspirations of claiming the K-1 Grand Prix title -- the most coveted martial arts title on the planet. Alistair is enormously popular in Japan so K-1 needs him for their fight cards. Potential showdowns again with Badr Hari, Remy Bonjasky and Peter Aerts are just three blockbusters that would sell out any venue for K-1. Alistair is a born fighter with a huge competitive spirit. He will not stop shooting towards a K-1 championship. MDS: I agree with Michael, and I'll even go so far as to say that I'm not 100% convinced Overeem will, in fact, fight Brett Rogers on May 15. There's a chance Overeem could get hurt against Poturak and be physically unable to fight six weeks later, but there's also a chance that Overeem could put on a spectacular performance against Poturak that would make the Japanese fans eager to see him again, quickly -- in which case it might make financial sense for him to pull out of the Strikeforce fight and keep fighting in Japan. 2. Semmy Schilt will be defending his super heavyweight title against Errol Zimmerman, who criticized Schilt as having a boring, robotic fighting style. Is that a valid criticism? Or should we just appreciate the Hightower as the best heavyweight kickboxer of his era? Michael Schiavello: No doubt Semmy is the most dominant heavyweight kickboxer of his era. In fact he is the most dominant fighter of any fight code in the world. That's a fact! But dominance does not necessarily mean you are aesthetically the best to watch. Look at Floyd Mayweather Jr., for example. He may be the best boxer in the world but is his style the best to watch? I don't think so. I appreciate that he makes use of his skill set and his speed, but Floyd's style of never-get-hit and counter strike with tremendous speed does not always translate into riveting fights. Likewise Semmy makes use of his God-given abilities, namely his incredible height, better than any other fighter out there. When you're a tall fighter you have to fight as a tall fighter and Semmy does that perfectly. He only really uses three weapons: a jab, a knee and a front kick. With his height that is all he really needs. He combines those three techniques with incredible cardio for a man of 120kg and the workrate of a middleweight. His style will never endear fans for flashiness but it gets the job done. It's all a matter of opinion, I guess: Do you like in-your-face, balls-to-the-wall fighters like LeBanner, Karaev and Hari? Do you like succulent technical fighters like Bonjasky and Spong? Or do you simply appreciate the dominance of a fighter like Semmy Schilt? MDS: I'm not sure I'd go quite so far as to call Schilt the most dominant fighter in the world, but I absolutely appreciate his dominance, and I think his style has gotten a bad rap. The way he tore through the 2009 World Grand Prix Final, needing less than six minutes, total, to win three fights, was a sight to behold. In some ways Schilt reminds me of Brock Lesnar, who also uses his incredible size to dominate his opposition, and in both cases, I'd rather admire what these guys do with their enormous bodies than nitpick about their fighting styles. 3. Kyotaro will defend his heavyweight belt against Peter Aerts. How meaningful is the K-1 heavyweight title? How important is it for K-1 that a Japanese fighter owns the belt? And how significant would it be for Aerts to win that title in the year he turns 40? Michael Schiavello: I think the idea of a K-1 heavyweight title is excellent but K-1 has failed to capitalise on it and make it an important title. It had more significance when Badr Hari held it but then he only defended it once against Glaube Feitosa. Badr was stripped of the title after the 2008 GP and Kyotaro won it in a shock result in a four-man tournament, which didn't make sense to me as the heavyweight title is meant to be a single-fight title. Kyotaro has yet to defend the title he won a year ago and comes in on a two-fight losing streak but is still the champion? I don't like that. I think K-1 very seriously needs to sort out this title and bringing in Peter Aerts could be the first step in doing so. Aerts is tremendously popular, moreso than Kyotaro, and is expected to win the title. Aerts is a very active fighter, even at 39, and will take great pride I am sure in defending the strap. It could set up Aerts vs Hari II which I know is a match Peter is itching for. MDS: In boxing, I think there are too many weight classes. In K-1, I think there are too few. I like the fact that K-1 has a heavyweight title and I also wish they'd add a title in the 85-kilogram (185-pound) range, which I think would be perfect for a Melvin Manhoef-style fighter. But I agree with you, Michael, that K-1 hasn't done enough with the heavyweight title. They could certainly do a lot with it if Aerts wins it and defends it against Hari, though.