Since being selected first overall by Saskatchewan in the 2016 CFL draft, the hulking offensive lineman has been introduced to the business side of football, changed positions and battled the injury bug. And since the Riders' playoff exit, St. John has seen the club make significant changes to its front office and coaching staff.
On Friday, the Riders promoted special-teams co-ordinator Craig Dickenson to head coach. Making that decision was Jeremy O'Day, who took over as GM/vice-president of football operations after Chris Jones resigned as Saskatchewan's head coach/GM to join the NFL's Cleveland Browns as an assistant coach.
"It's been eventful three years but that's OK because I've definitely enjoyed my time in Saskatchewan, for sure,'' St. John said Monday. "I think it (Dickenson hiring) is a good move because the players in the locker room respect him, he's a good coach.
"I feel it was a long time coming for (Dickenson) getting a head-coaching job. It's a seamless transition ... he knows how we are, we know how he is. I'm definitely excited for him and the season in Riderville.''
St. John's tenure with Saskatchewan began well enough, with the CFL club taking the native of Ajax, Ont., first overall in the 2016 Canadian college draft out of the University of Oklahoma. But then came a contract impasse that resulted in the six-foot-five, 309-pound St. John missing training camp, the pre-season and the Riders' first regular-season game before signing a three-year deal (two plus an option).
"That was definitely an eye opener,'' he said. "That was my first time, really, being exposed to the business side of football.
"I mean, I played Division 1 football so obviously they called it the politics side in college. But it was frustrating at the time because I wanted to play but I had to let my agent (Jonathon Hardaway) do his job.''
When St. John finally joined the Riders, he began practising at right guard instead of tackle, where he'd played throughout his college career. Still, he appeared in 10 regular-season games (six starts) that year.
But injuries have limited St. John to just 12 games the last two seasons. After appearing in just one contest in '17 - partly due to the presence of an abundance of veteran offensive linemen - St. John missed the first six games of last year while on the injured list.
He returned to play 11 regular-season games (two starts) and start in Saskatchewan's 23-18 West Division semifinal loss to Winnipeg. St. John is poised to become a free agent Feb. 12. But his preference is to remain with the Riders, who finished second in the West Division last year with a 12-6 record.
However, Saskatchewan has twice had to shuffle its front-office this off-season. In December, the CFL club and assistant GM John Murphy parted ways after Murphy reportedly refused to take a 10 per cent pay cut as part of the Riders complying with the CFL-mandated football operations salary cap.
Then Jones, a week after signing a contract extension with the Riders, left Jan. 15 to join the Browns.
"I definitely would like to go back to Regina, that's kind of the plan right now,'' St. John said. "It's been pretty tough because we negotiated with John Murphy and he's gone, then we negotiated with coach Jones and he's gone.
"Now it's with Jeremy O'Day.''
Many players heading into free agency embrace the opportunity to dictate their career path and find out their worth on the open market. But the 26-year-old St. John isn't one of them.
"The simple fact is I like to know where I'm going next year, who my teammates are,'' he said. "I don't know where I'll be next year, what jersey I'll be wearing, where I'll be living.
"It (free agency) is a weird feeling the first time going through it.''
In free agency, St. John could entertain offers to play closer to home. While he'd enjoy being able to play before family and friends more often, St. John has become used to life away from home, playing collegiately in California, Texas and Oklahoma before arriving in Regina.
"It would be cool to have my family be able to go to all of my games but it's not really high on the priority list,'' he said. "I guess we'll have to see what happens.''