Gilbert Melendez thinks he's the best lightweight in mixed martial arts. Is he right? I don't think so, not yet. But I sure would love to find out.

The best thing about the UFC buying Strikeforce is that it means we'll eventually see the champions of the respective promotions fighting each other. For now the mantra is "business as usual," but we all know it's just a matter of time before we see the best of Strikeforce inside the Octagon. And there might not be a better fight out there than Melendez taking on the top of the UFC lightweight division.

It will probably be 2012 before we get to see that: UFC lightweight champ Frankie Edgar has to fight Gray Maynard in May, and the winner of that fight is expected to fight the winner of the June Anthony Pettis-Clay Guida bout after that. But it sure would be fun to see Melendez retiring the Strikeforce belt to his trophy case and fighting for the UFC gold.

Find out where I think Melendez stacks up in the lightweight division below.

(Editor's Note: The fighter's rankings the last time we ranked the lightweights are in parentheses.)

1. Frankie Edgar (1): The UFC champion remains at the top of the heap at least until he fights Gray Maynard at UFC 130. The third meeting between the two will, I hope, tell us once and for all which one of them is really the superior fighter.

2. Gray Maynard (2): Maynard could certainly make the argument that he actually deserves to be ranked ahead of Edgar, since Maynard beat Edgar the first time these two fought. I'll stick with Edgar for now because Edgar's overall lightweight resume is more impressive, but these two are basically equals.

3. Gilbert Melendez (4): Now that Melendez has destroyed Tatsuya Kawajiri, I think he's behind only the UFC lightweight champion and No. 1 contender. I love watching Melendez because he's so active and tenacious: He took the fight to Kawajiri and showed off a great killer instinct in finishing him with the recently legalized elbows to the head on the ground. The question now is whether any lightweights on the Strikeforce roster can even be viewed as credible threats to Melendez, or if he's going to have to start fighting guys in the UFC.

4. Kenny Florian (3): For now, I'd pick Florian to beat just about any lightweight in the sport. But Florian has lost two lightweight title fights and doesn't appear close to getting a third chance, Rift Gold so he plans to drop down to featherweight and pursue the belt there. When he does move down to featherweight, I'll take him down the lightweight list -- and I expect him to quickly rise up the featherweight ranks.

5. Shinya Aoki (5): There really wasn't any question that Aoki would make quick work of Lyle Beerbohm, but there are a lot of questions about Aoki's future: Will he stay with Strikeforce and keep fighting second-rate opponents? Will he go back to Japan and try to be a part of revitalizing the MMA scene in his homeland? Will he finally step into the Octagon?

6. Jim Miller (8): It's time for Miller to take a major step up in competition: His 20-2 record consists of wins against a bunch of guys who aren't even close to the Top 10, and losses to the two best in the world, Edgar and Maynard. Ideally I'd love to see Miller against Melendez or Aoki, but if we're not going to get UFC-Strikeforce crossover fights yet, Miller probably will continue fighting overmatched opponents outside the Top 10.

7. Eddie Alvarez (7): The Bellator champ is a lot of fun to watch, but it's going to be awfully tough for him to move up in the rankings as long as he remains in Bellator, which just doesn't have any elite opposition for him to face. Alvarez may have the talent to beat anyone at 155 pounds, but he's probably going to have to sign with the UFC if he wants to prove it.

8. Anthony Pettis (10): The thing that's so exciting about Pettis is that he's doing so many new things at such a young age. RIFT Platinum It's not just the "Showtime Kick," although that's obviously what he's best known for: It's a combination of creative striking and an aggressive ground game, especially off his back, that makes Pettis different from any other fighter in the lightweight division. The 24-year-old Pettis is the youngest fighter on this list and is only getting better.

9. Clay Guida (NR): Guida has always been a fan favorite because of his brawling style, but it's been somewhat overlooked that his technique,rift gold especially on the ground, has noticeably improved in the last year. Guida is now on a three-fight winning streak, and if he makes it four in a row against Pettis, a title shot could be next.

10. Tatsuya Kawajiri (9): Kawajiri has had some great wins in his MMA career, but he was simply no match for Melendez. At age 32, he appears to be on the down side of his career, but there are still some fun fights for him: I'd still love to see a rematch of the classic 2005 Pride fight between Kawajiri and Takanori Gomi.
Read More: UFC WEC Strikeforce Bellator Rankings Lightweights Anthony+Pettis, Clay+Guida, Eddie+Alvarez, Frankie+Edgar, RIFT Platinum Gilbert+Melendez, Gray+Maynard, Jim+Miller, Kenny+Florian, Shinya+Aoki, Tatsuya+Kawajiri

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