Devlin was named club captain at the weekend, with Bartley stepping back somewhat from playing duties after being appointed as David Martindale's assistant.
The 27-year-old was handed the armband after signing a new contract that ties him to the club until the summer of 2023.
"I'm delighted to be secure here for the next two seasons at least and the captaincy was a massive honour," Devlin said ahead of the cinch Premiership clash with Motherwell.
"Davie and the rest of the coaching staff showed a lot of faith in me giving me the captaincy so I am going to have to repay them with performances on the park and try and lead the boys as best I can.
"I will almost try and replicate Marv. He was a fantastic leader for us last year.
"Unfortunately I don't speak as well in front of a camera as Marv, that was one of his strong points, but the way he conducts himself, if I can replicate that then I know I will feel I am doing my part because Marv was brilliant last year for all the boys.
"That's what the main role is, to be there for the team when maybe stuff isn't going so well for us on the park."
The double boost for Devlin was a welcome lift after a difficult start to the season.
The full-back injured himself at the start of pre-season when sliding into a tackle and missed the Premier Sports Cup group campaign after being hit by another piece of misfortune.
"I think it was the second day," Devlin said. "I broke my ribs and ended up with a puncture in my lungs.
"On the sheet I got from hospital it said collapsed lung, and when I showed that to my mum she was panicking straight away. But I was lucky, it was only a small amount of air that escaped.
"That was me out for four weeks, then just as I was coming back, after a couple of days of non-contact stuff, I tested positive for Covid. So that was another 10 days in the house.
"It's not been ideal but it's going to happen to teams throughout the season."