The Blue Jays have designated lefty Felix Doubront for assignment, Ben Nicholson-Smith of Sportsnet.ca reports on Twitter. The move creates roster space for the activation of Troy Tulowitzki.

Still just 27 years of age, Doubront was not long ago looked at as a potential rotation piece for the Red Sox. He topped 160 innings in both the 2012 and 2013 seasons with Boston, working to an overall ERA of 4.59. While that mark isn’t terribly impressive, he showed a good ability to miss bats (8.5 K/9) in addition to a ground-ball rate of roughly 44 percent, both of which helped to partially offset his questionable control (4.0 BB/9). Sabermetric marks like FIP and xFIP pegged his talent level closer to 4.00 than his 4.59 ERA.

Doubront’s velocity has declined, though. After averaging 92.7 mph in 2012, he averaged 90.5 mph in 2013 and has seen his fastball hover around 90 mph since that time. This season with the Blue Jays, he pitched to a 4.76 ERA with a 13-to-5 K/BB raito in 22 2/3 innings. While the sample was brief, Doubront did see a massive spike in his ground-ball rate, which soared to 64.6 percent. He’s utilized a cut fastball far more in 2015 than he did in 2012-13, perhaps signaling a change in his approach on the mound.