Kind of expected Curtis to have a stiffer matchup than this... he just KTFO'd Brendan Allen who many consider a borderline Top 15 guy. And before that he beat Phil Hawes who is a decent Middleweight (though sometimes slightly overhyped IMO).
I expect Chris to clean up here. He's way too much of a veteran to fall prey to someone whose overall MMA game and cage sense is still relatively infantile like that of Vieira. I really liked seeing the development of an accurate, crisp piston of a jab into Rodolfo's game. That shit was absolutely on-point against Stoltzfus. However, despite that, Chris is still the vastly superior boxer of the two and Rodolfo still looked quite uncomfortable on the feet even when he was winning the exchanges handily.
When it comes to grappling, obviously going to the mat with Vieira will be trouble. But in a fight spanning 39 combined professional and amateur bouts, Curtis has been submitted only once back in 2011. He's a BJJ Purple Belt and has three submission wins of his own. The fight with Fluffy showed that a veteran with sound defensive Jiu-Jitsu, good scrambles, and great awareness is able to survive bad situations on the mat against Rodolfo and weather the early storm. But I'm not even convinced the fight gets there, honestly -- Phil Hawes (decorated wrestler) and Brendan Allen (solid all-around offensive grappler) shot three takedowns each on Curtis stuffed every single one of them. He still has 100% TDD in the UFC and even in his pre-UFC career he was known for having solid defensive wrestling.
My only real concerns for the Action Man is that he's an undersized Middleweight (could easily make 170 and has many times in the past IIRC) fighting a gargantuan of a man who will be attempting to manhandle him in grappling exchanges -- not to mention the fact that Vieira also packs a decent punch when he wants to. But other than that, Curtis is better in every area that matters.
Action Man by KO/TKO Rd 3. Vieira is going to trade a few jabs with him early but be clearly shook of the stand-up before wrestling himself into exhaustion trying to unsuccessfully drag Curtis down and hold him down. There might be a tricky spot or two where he briefly succeeds and Chris has to fight off a submission attempt. However, by the halfway point of Round 2 Rodolfo will be sucking air and Curtis is going to apply a lot of pressure with his boxing, walking him down, parrying/countering his jab, and stuffing his increasingly bad TDs before finishing him late. Using his fight IQ, weaponized cardio, defensive grappling, and pressure-boxing to win Decisions or score late KO/TKOs (based either on attrition or capitalizing on his opponents making mistakes) is actually more of what he's known for. Him being some early rounds knockout artist is a relatively new development.
Unfortunate, as I actually like Vieira way more than Curtis and have something of a (admittedly unfair) bias against the latter. I keep expecting him to get derailed. But Rodolfo ain't the guy to do it.