Kameron Kelly's 2019 has been eventful, to say the least. 

Six months ago, he was playing cornerback and receiver for the San Diego Fleet of The Alliance of American Football. Five months ago, he was signed by the Pittsburgh Steelers after the AAF closed shop. On Sunday, Kelly, who made Pittsburgh's 53-man roster as a backup free safety, may start Pittsburgh's first game of the season against Tom Brady and the New England Patriots. 

On Friday, the Steelers listed staring free safety Sean Davis as doubtful as he continues to deal with an ankle injury sustained in Pittsburgh's third preseason game. Kelly spent the week filling in for Davis as he worked with Pittsburgh's first string defense. 

"Yeah, I mean it'll be a lot of fun," Kelly told reporters earlier this week, via Jacob Klinger of PennLive.com. "I've been preparing for this since I was a little kid, so I'm trying not to think about it or make it too big of a deal."

A former high school quarterback, the 6-foot-2, 205-pound Kelly switched to receiver after starting his collegiate career at San Diego State. He then saw time at both safety and cornerback during his final three seasons with the Aztecs, picking off nine passes while breaking up 15 others to go with 164 tackles and two forced fumbles. 

Kelly was initially signed by the Dallas Cowboys last spring as an undrafted rookie. After not making Dallas' 53-man roster, Kelly made the most of his opportunity in the AAF, receiving a call from the Steelers shortly after the league folded. Kelly immediately showed what he could do in Pittsburgh, earning first-team defense reps during OTAs with Davis sidelined with an injury. Kelly could also be used as a linebacker in dime situations. 

After continuing to impress over the summer, Kelly earned a spot on Pittsburgh's 53-man roster. But despite his solid play throughout camp, Kelly wasn't sure whether or not he'd make the cut. This past Saturday, when teams are required to trim their rosters to 53 players, Kelly said he waited for a phone call that never came. 

"I wasn't told anything. I just sat at home, waiting for a call," Kelly said, via Chris Adamski of the Pittsburgh Tribune-Review. "I didn't get one, and I was sure happy.

"I am thankful for the opportunity, and I feel like I made the most of it. And now I've got 16 more opportunities."

Kelly's first opportunity will come against Brady and the Patriots. The Steelers have never beaten a Brady-led Patriots team in New England and are 1-5 against Bill Belichick in Foxborough. 

"Everybody is confident in him," Pittsburgh cornerback Mike Hilton told the Tribune-Review. "He has shown that all offseason. He can go get the ball for us. That's something as a defense that we thrive on. Everybody on defense is confident in him if he starts. If not, he'll be ready if 'SD' can't go the whole game."