Diaz is coming off a one-year suspension (which expires in February 2013) after testing positive for marijuana metabolites following his last fight against Carlos Condit.
While some fans are wondering why GSP is going to fight Diaz instead of somebody who is riding a winning streak, such as Johny Hendricks, this matchup appears to be more compelling.
Many experts believe GSP is going to be able to pull out another decision victory (10 of his 18 wins in the UFC have come by decision) over Diaz. Considering the welterweight champion hasn't lost a fight since 2007 and only two in his entire 11-year career, it's hard to argue against them.
That's exactly what we're doing here. I firmly believe Nick Diaz is going to beat GSP and become the next welterweight champion.
Here are three reasons why.
When one looks back on Nick Diaz's career thus far, how many times can you remember him being held on the ground for an extended period of time?
Carlos Condit beat Diaz earlier this year, but that was because Condit was able to get close enough to attack and immediately get out of harm's way before Diaz could land significant strikes.
Sure, Condit seemed to bicycle away from Diaz, but I wouldn't call it running away. He had a game plan, stuck to it and won the fight.
GSP is arguably the smartest fighter in the sport and certainly knows how to get out of the way of a counter right after he lands something on his opponent. He won't avoid Diaz in the same way Condit did, however. GSP will engage in more of a battle and rely on a strike/takedown combo instead of backpedaling away from Diaz.
Diaz will be able to utilize his refined Brazilian jiu-jitsu skills to avoid getting into bad positions after a GSP takedown. Diaz may land on his back once or twice, but he will not allow GSP to pull the "lay and pray" that we've seen him do time and time again.
Let's be perfectly clear—GSP is aggressive while on top of his opponent. But he still relies heavily upon controlling his opponent on the ground by smothering him so he can't get back to his feet. It's not a Jon Fitch "lay and pray" by any means, but it's effective nonetheless.
If GSP does manage to get Diaz down, it won't be for long, and Diaz will be back on his feet faster than most expect.
Why are those numbers significant?
In the last five years, Nick Diaz has been involved in 12 professional fights. He has won 11 of those, lost one and has not been knocked out.
Over the span of his 11-year career, he has lost by knockout only twice.
The first instance was early in his career in 2002 against Jeremy Jackson, whom Diaz went on to beat twice just one year later.
Most recently, he lost in 2007 against K.J. Noons. The TKO loss to Noons was actually due to a doctor's stoppage (cuts). Diaz also avenged that loss in 2010.
Of course, anyone can point to those two losses against Jackson and Noons and say that if those two fighters can knock out Diaz, then surely GSP can. Diaz, however, has become a much better fighter over the last five years, and his chin has remained intact.
I recall watching him fight Paul Daley in April of last year. Daley landed a punch flush on Diaz's chin, Diaz hit the deck and he withstood a flurry by Daley. This happened twice in the first round. Diaz got up and looked stronger than ever. He managed to win that fight with a few seconds left in the same round.
If GSP does find a way to win, it won't be via knockout.
Nick Diaz is a professional boxer inside an MMA organization.
The way Diaz had his way with BJ Penn is exactly the type of performance he is going to need to have against GSP in order to win this fight—and I think he's going to do just that.
Diaz landed an insane amount of strikes in the fight, somewhere right around 180. That's nearly 100 more than BJ landed in return.
GSP avoids a lot more strikes than BJ does. Overall, GSP has avoided 76 percent of his opponents' strikes. Diaz will have to focus on quick combinations to wear down the champion toward the fourth and fifth rounds of the fight.
This fight will reach the fifth round and more than likely go to a decision. Both of these great fighters have world-class stamina, and neither one will submit to the other.
Diaz learned a lot from his loss to Condit. He knows others, more specifically GSP, may look at that as a blueprint to how to beat him. He's not going to let GSP duck in and out the way Condit did, but at the same time, he will land more significant strikes throughout this fight that promises to go the distance.
Of course, who knows if the judges would even give Diaz the win in Canada? If Diaz loses another decision that he feels he won, he may walk away from the sport completely.
Prediction: Nick Diaz wins via split decision (49-46, 47-48, 48-47)
Joe Chacon is a featured columnist for Bleacher Report and a staff writer for Operation Sports. You can follow him on Twitter @JoeChacon.