JDS has the better stand up...but can he withstand Cain's relentless wrestling??? That's the question, he hasn't had to work of his back, so who knows how well he can handle that type of pressure..if he stays off his back I think he beats Cain.
I don't think cain will have much ring rust. The guy is a machine in the gym and doesn't let himself get out of shape like rampage or Forrest. Regardless, I think JDS will avoid cain's takedowns in the first couple rounds and T/KO him. Also, the longer it goes, the more favorable it becomes for Cain so JDS better get working early 
Cain
Junior no offence to cain but hes got "cage rust"? Idk its something along those lines and also cain is coming off an injury unless junior has really bad takedown defence (which he doesent) then i dont see cain winning the fight
I think JDS can avoid being taken down, but I'm not so sure he can deal with the pace and cardio for five rounds. Makes me lean towards Cain.
Yeah gotta back Cain .. The mans a beast , jds looked impressive as hell against against Carwin, if it was a 3 round fight I'd say junior could take a decision, but being 5 rounds I fancy Cain to get the tko in the 4th or 5th !
Cain.
Cain cannot take punches from jds he got dropped twice by Kongo ! I no Kongo has power but jds is alot faster than Kongo so he will surely get the belt
Anyone picking either of these guys with "no doubt" or "easily" or "definitely".........is a retard.
Whoever wins, wins 50% of the time, and loses the rematch if there is one.
Junior had no trouble with his wrestling in any other fights because his footwork is good and wen people feel his power they move back and he does the stalking Cain will fall to the hands of dos santos ! He's the no1 guy in the hw devision cain is a gd striker junior is world class striker !!
I am a huge JDS fan but IMO Cain is just on another level compared to everyone else in the UFC right now.
Pretty confident Cain takes this.
cain by wrestling
Easy pick for me, Cain. Looking at some replies I think a lot of people still don't realise just how good he is. Dos Santos isn't stopping his takedowns, not a chance. I'll be surprised if he has anything left by the 3rd round, and Cain will still be fresh.