Hyun Jin Ryu has been placed on the 10-day injured list with neck tightness, the Blue Jays announced Sunday.
Ryu will be eligible to return September 28, and he's expected to miss only one start. Left-hander Tayler Saucedo was recalled from Triple A Buffalo in a corresponding move.
The injury designation provides some clarity for Ryu's immense struggles lately. After a solid first half, the 34-year-old has posted a 5.61 ERA in the back half of the year. Over his last five starts, he's allowed 22 runs in 19 2/3 innings, good for a 10.07 ERA.
On Friday, Blue Jays manager Charlie Montoyo mentioned the possibility of skipping one of Ryu's starts to give him a breather, so there's a good chance Toronto was prepared to move forward with a four-man rotation over the next few weeks anyways.