Villarreal will not be tendered a contract by the Reds, C. Trent Rosecrans of the Cincinnati Enquirer reports.
His 3.42 ERA in 2015 was more than 50 points below the Reds' collective bullpen mark, but the peripherals suggest he overachieved. While he improved his control, Villareal had a 5.2 K/9 and a below-average groundball rate, with his FIP coming in a full run higher than his ERA.