The Rockies have outrighted left-hander Tyler Matzek, per a club announcement. He has already cleared waivers.
Colorado added Matzek, now 25, with the 11th overall pick in the 2009 draft. Once a consensus top-fifty prospect, he fell somewhat off of the radar while struggling to keep the ball in the strike zone.
Matzek seemed to right the ship in 2014, when he tamped down his persistent control issues and reached the majors for the first time. He provided the Rockies with 117 2/3 rather good innings that year, putting up a 4.05 ERA with 7.0 K/9 against 3.4 BB/9 and a 49.7% groundball rate.
That all reversed in 2015, however. Matzek completely lost his ability to hit the zone and ended up taking a long reprieve to address serious anxiety issues. He has been working back slowly since; over ten frames this year, all at the High-A level, Matzek has allowed just two earned runs on six hits, though he also has seven walks to go with his 14 strikeouts.
Matzek will obviously remain with the organization and keep trying to build himself back toward the majors. It does not appear that Colorado needed a 40-man opening at this exact moment, since it now has an open slot, but perhaps felt this was an opportune time to make the move.