The Detroit Lions claimed the former Concordia Stingers star off waivers Friday, a day after he was released by the Kansas City Chiefs.
Barker selected Greenwood in the first round, third overall, of the 2010 CFL draft. But Greenwood never arrived, instead signing with Kansas City.
The 27-year-old native of Kingston, Ont., cracked the NFL squad's roster as an undrafted free agent. He spent three seasons with Kansas City before being released Thursday.
But Barker wasn't expecting the six-foot-two, 235-pound Greenwood to beat a path to Toronto.
"I want him to exhaust all of his NFL options and do what's best for him," Barker said prior to Greenwood being claimed. "When he comes here we want him to be committed and excited about being here and turn the page.
"We don't want him thinking, 'If I had just waited a little bit longer.'"
Greenwood played 48 games with Kansas City, mostly on special teams. He recorded 10 tackles, one forced fumble and one fumble recovery in 16 contests last year and over three NFL seasons, accumulated 34 career tackles.
It makes financial sense for Greenwood to continue playing south of the border. The NFL's minimum salary for a four-year veteran this year is US$730,000.
Greenwood played at Concordia from 2006 to '09. In his final season, he captured the Presidents' Trophy as Canadian university football's top defensive player.
While Greenwood will get a second chance in the NFL, Barker says his enthusiasm for former Concordia star hasn't dampened.
"You're looking at a guy who'd become a dominant player in this league," Barker said. "He's got experience and he'd be a better player now than he would've been three years ago."
Barker has never been afraid to take a chance with his draft picks.
In 2011, Barker traded into the first round for Tulsa offensive lineman Tyler Holmes even though he was remaining in school. Last year, Barker drafted Iowa State defensive lineman Cleyon Laing, Northern Colorado linebacker Herve Tonye-Tonye and Rice tight end Luke Willson knowing all three were headed back to their respective universities.
Holmes spent last season on the Minnesota Vikings practice roster while Laing is attending the Oakland Raiders mini-camp, which began Friday. And last weekend, Willson went in the fifth round of the NFL draft to the Seattle Seahawks.
"When you take good players you risk losing them," Barker said. "If Luke Willson wasn't drafted by Seattle, he was all set to be a Toronto Argonaut.
"But things worked out great for him and we're really happy for him."