Kansas City would call Ventura back up to the majors just one day after his demotion to Triple-A Omaha, as he will have to fill a hole in the rotation. The Royals initially sent him down to have him work on consistency following his injury. Ventura will start on Sunday against the Houston Astros.
The 24 year-old is 4-7 with a 5.19 ERA in 14 starts this season.
Vargas started on Tuesday against the Pittsburgh Pirates, but left that start in the second inning after just 26 pitches. An MRI on Wednesday revealed the tear of the UCL.
The Royals' right-hander has been on the disabled list twice this season with elbow injuries, and made his return from the DL on Tuesday.
Vargas was 5-2 with a 3.98 ERA this season, and was a key component in the Royals' postseason run last season. He went 1-0 with a 3.52 ERA in three postseason starts. He is in the second year of his four-year, $32 million deal.