When he entered the league as the 73rd pick last year, the idea that he'd be ahead of Foster and a slew of other All-Pro backs halfway through his sophomore season wasn't a thought.
"I just go out there and run the football," he said, "and I look up right now . leading the AFC in rushing? It's a dream come true for me."
The same could be said for the Patriots (5-3).
Led by quarterback Tom Brady, one of the most potent and pass-happy offenses in the league over the past five years has now morphed into a more balanced attack behind the straight-ahead running of Ridley.
With 150 carries through the first eight games, fifth most in the league, Ridley is on pace to become the first New England running back with at least 300 since Corey Dillon notched 345 in 2004. In fact, only BenJarvus Green-Ellis (2010) and Dillon (2004, 2005) have eclipsed 200 carries for the Patriots in the last nine years.
"He's very passionate about the game. Stevan loves to play. I think that's his biggest asset," New England running backs coach Ivan Fears said. "On game day, he is there. He is mentally in the right frame of mind to play the game and I think as long as he's got that kind of passion for the game, he's going to do the little things that he needs to do to be physically ready to play.
"He's figuring out how to be a professional athlete, he's figuring out what it takes to win on Sunday. That's what you like about him."
After carrying the ball just 87 times for 441 yards during his rookie campaign, Ridley this season has made some serious strides, exhibiting the intangibles required to thrive at this level.
His power, speed and elusiveness all have been on display at one time or another during an array of dazzling runs, including a league-leading 47 for first downs, five that have gone for 20 or more yards and five that resulted in touchdowns.
"I've got a lot of work to do in front of me," he said. "I'm looking forward to the next eight (games) that we have."
Patriots coach Bill Belichick thinks so, too.
"I think he's done some good things. I think there's certainly a lot of things that he can improve on," he said. "There's been times where he's had really good blocking. There's times where he's produced yards on his own. There's a lot of things that he can work on. He's still a young, improving player."
So far, so good, though. And his body seems to be holding up well to the rigors of being the primary back.
"I'm still playing football and still on the field. As long as I'm not missing any playing time, it's 100 percent," Ridley, 23, said. "Like I said, I'm just thankful to be healthy and thankful to be in my position in where I am. Got a little bit of football left to play, hopefully I can be healthy all the way until the end."
The Patriots certainly hope so.