"I would like to thank everyone involved with my CFL career, especially the Hamilton Tiger-Cats organization, for four great years that I will never forget," Barker said in a statement. "I couldn't have had better teammates, coaches, managers, and mentors, or played in front of better fans.
"When I was drafted four years ago, I envisioned having a healthy, long career in the CFL. Unfortunately, due to unforeseen injuries I can no longer continue my football career and will now pursue interests outside of football at the University of Saskatchewan. Again, I'd like to thank all of TigerTown for four of the most memorable years of my life."
Hamilton selected Barker, a native of Moose Jaw, Sask., first overall in the 2008 CFL Canadian college draft. The former Saskatchewan Huskies star missed the 2008 campaign with a leg injury but posted a CFL-record 37 special-teams tackles in 2009 while adding six tackles and an interception.
He started 13 of 17 regular-season games in 2010 before missing all of last year with a back injury. Barker, who will look now to become a dentist, registered 40 tackles, 51 special-teams tackles and four interceptions in 35 CFL contests.
"It's very unfortunate to see Dylan's promising football career end at such an early age," said Bob O'Billovich, Hamilton's vice-president of football operations. "During his time in Hamilton, he was a positive contributor on and off the field who represented the club with strong character.
"We wish him nothing but the best as he begins his new career.''
Meanwhile in Toronto, the Argonauts announced they're on the lookout for a new offensive co-ordinator.
When Scott Milanovich became Toronto's new head coach in December, one of his first moves was to hire Jonathan Himebauch as his offensive co-ordinator. But on Wednesday, the Argos announced Himebauch has accepted a coaching position with an NCAA school.
“When we signed Jonathan, we allowed him a window to pursue collegiate jobs," Milanovich said. "Jonathan found a lucrative position with potential for growth and we wish him continued success.
"Knowing this was a possibility, we have been working on an alternate plan and expect to have more announcements shortly.”
The Calgary Stampeders bolstered their coaching ranks by announcing that defensive lineman DeVone Claybrooks has retired to become the club's defensive line coach.
Claybrooks, 34, spent the past three seasons with the Stampeders after playing the first two years of his CFL career with the Montreal Alouettes. Overall, Claybrooks appeared in 75 regular-season games, registering 161 tackles, 14 sacks and two fumble recoveries.
“Moving into the coaching ranks is a natural progression in my career,” said Claybrooks. “My goal was to coach and to be able to stay in Calgary, so I'm obviously thrilled.”
The Stampeders also unveiled the remainder of their defensive coaches, with Dave Walkosky being promoted to defensive co-ordinator after serving as the team's linebackers coach in 2011. As well, Tony Missick returns for a second season as defensive backs coach.
The club also announced it has signed veteran slotback Chris Bauman, a native of Brandon, Man., who was recently released by the Edmonton Eskimos. Bauman is entering his sixth CFL season and spent the first four years of his career with Hamilton, who selected him first overall in 2007 out of the University of Regina.
The Edmonton Eskimos released four players, including veteran kick-return Jason Armstead and defensive back Jykine Bradley.
An eight-year CFL veteran, Armstead spent parts of the past two years with Edmonton. He appeared in 12 games last year, registering 62 punt returns for 486 yards and a touchdown while returning 35 kickoffs for 684 yards.
Armstead suited up for just three games with Edmonton in 2010.
Bradley signed as a free agent with Edmonton prior to the 2011 season. He started 17 games and recorded 31 tackles, two interceptions and two fumble recoveries.
The Eskimos also released offensive lineman Chris Patrick and defensive lineman Joe Sykes while signing defensive back Michael Ricks.