But the quarterback hopes to stay involved in football after officially calling it quits Tuesday.
"I'd love to look at those opportunities as they arise," Pierce said in an interview from his Winnipeg eatery. "(Football) is my passion. I've always been a student of the game and looked up to coaches.
"Obviously, (the passion doesn't end) just because you stop playing. That competitive fire will never burn out."
Pierce split last season between the Lions and the Winnipeg Blue Bombers, throwing for 1,176 yards, five touchdowns and seven interceptions. Over nine seasons with Winnipeg and B.C., he completed 1,200 passes for 15,289 yards, 76 TDs and 63 interceptions.
"I feel pretty good about (retiring) actually," he said. "I feel that, over the last nine years, it's been a great career for me. I enjoyed every minute of it. The teammates, the organizations were the part that were great experiences for me. It's a hard day also, in a way, for me because it's what I've known. It's what I've been about for the most part of my life.
"So it's a big day in both ways. But I'm also excited about the next phase of my life and moving on."
Pierce, a 32-year-old Hutchinson, Kan., native who played collegiately at New Mexico State, originally signed with the Lions in 2005. He was a key member of the club as both a backup and starter through five seasons before playing 3 1/2 seasons with the Blue Bombers.
He returned to B.C. last September in a trade that brought wide receiver Akeem Foster to Winnipeg.
"Buck was a fearless competitor who never hesitated to put his body on the line for our organization," Lions general manager Wally Buono said in a news release.
Pierce's career was marred by multiple injuries as he chose to take a hit instead of sliding or running out of bounds before getting tackled. But he said the rewards were worth the punishment.
"I wouldn't change anything I played the game the way that I felt this game should be played, and I felt that I represented myself extremely well on and off the field," he said. "There's always going to be critics, and people are going to say what they're going to say, but at the end of the day, I represented myself and my family and this league in a positive way."
He won a Grey Cup with the Lions in 2006 and led the Bombers to the 2011 championship game, where they lost 34-23 to B.C.
"Obviously, winning the Grey Cup in '06 was a big point in my life," he said. "There's lots of memories. You don't necessarily remember all of the big wins and stuff like that. But when you play almost a decade, you have lots of teammates and you see lots of teammates be traded and all these things, so you have lots of memories that stick with you.
"Obviously, when I helped the Bombers get to a Grey Cup in Vancouver, that was a big part, and I felt very good about what we accomplished that year."
His final CFL campaign, when he was relegated to third-string status with the Blue Bombers before being dealt, was "extremely difficult."
"But it's all about what he you take away from situations and what you learn," he said. "I was fortunate enough to get traded to B.C., where it all started, and I had some great games at the end of the year. I'm privileged and excited to be retiring as a Lion."
Pierce had "extremely minor" arthroscopic surgery on his shoulder following the season and would have needed to get another contract from the Lions. But neither his health nor contract issues affected the decision to retire.
"I didn't know what was going to happen (after) last year," he said. "I wanted it to be my decision. It wasn't money. It wasn't about injuries. It wasn't about anything else. It was about where I was at my point in my career and moving forward and taking that next step — and about taking advantage of some of the opportunities that I have out there."
Noting he had reached a state of contentment, Pierce expressed gratitude to fans, teammates and his two clubs alike.
"The CFL and Canada have been great to me," he said. "I've been fortunate to have amazing teammates, great mentors all throughout my career, and have played in great cities in the league — and became a part of the culture here in Canada."
He and his wife Lori, who is from Winnipeg, live in the Manitoba capital and plan to reside there until the future opportunities take them somewhere else.
"Winnipeg's the place that I call home right now," said Pierce.
After announcing Pierce's retirement, the Lions also announced the signings of quarterbacks John Beck and Jarrett Lee.
Pending any early cuts following a mini-camp, the Lions are slated to have five quarterbacks at training camp in June in Kamloops, B.C. In addition to starter Travis Lulay, whose recovery from off-season shoulder surgery is considered ahead of schedule, the Lions have holdover QBs Joey Elliott, the apparent No. 2 at this point, and second-year pro Chris Hart.