One of the Toronto Blue Jays' top pitchers will miss at least one start as they try to secure an MLB postseason spot after ace Ryu Hyun-jin landed on the injured list.

The in-form Blue Jays placed Ryu on the IL on Sunday due to neck tightness following a second consecutive difficult outing. 

Ryu lasted a season-low 2.1 innings in a September 11 game against the Baltimore Orioles after complaining of tightness in his forearm following his previous start. 

The 2019 All-Star followed it up by going only two innings in a loss to the Minnesota Twins on Friday and felt discomfort in his neck on Saturday.

Ryu allowed a total of 13 hits and 12 runs across those two outings as his ERA ballooned from 3.77 to 4.34. 

Blue Jays general manager Ross Atkins told reporters Ryu did not feel the neck issue while he was pitching and said Toronto expect the 34-year-old pitcher to miss only one start. 

"At this point in the season we didn't want to just push through," Atkins said. 

The Blue Jays recalled reliever Tayler Saucedo from Triple-A Buffalo to fill the veteran's roster spot, and manager Charlie Montoyo said the team likely would turn Ryu's next scheduled start at the Tampa Bay Rays on Wednesday over to the bullpen. 

"He's been one of our aces the last few years," Montoyo said. "Hopefully this won't take that long."

The Blue Jays have won 18 of their last 22 games following Sunday's 5-3 success against the Twins and lead the New York Yankees by a game and a half for the final American League (AL) Wild Card spot.