The 36-year-old reliever will be a cheap option for the Royals, who are in second place and 6.5 games back of the Detroit Tigers in the AL Central entering the second half of the season. Frasor has an ERA of 3.34 in 29 2/3 innings with Texas this year. He will only cost Kansas City $1.75 million for the remainder of the 2014 season.
Kansas City has a team ERA of 3.76 this season, 11th in Major League Baseball.
According to The Dallas Morning News, Patton will be assigned to Triple-A Round Rock. He has a 4-3 record and 4.08 ERA in 34 appearances in Triple-A Omaha this season.
The Rangers have not announced who will fill Frasor's spot on their 25-man roster.
- Sarah Barshop