Jon Heyman of CBS Sports reports that the contract is worth $4.15 million — $1.6 million next season and $2.55 million in 2016. In reaching the deal, the two sides avoid arbitration.
Herrera pitched 70 innings in relief for the Royals last season, compiling a 1.41 ERA with 59 strikeouts. The 25-year-old did not allow a home run all season.
In Kansas City's postseason run, Herrera gave up three earned runs in 15 innings, striking out 16.
The Royals earned their first playoff berth since 1985 in 2014, reaching the World Series before losing to the San Francisco Giants in seven games.
- Molly Geary