Herrera was called up to MLB for the first time on September 21, 2011.[3] That day, he gave up three earned runs over two innings, against the Detroit Tigers.[4] He made one other appearance, on September 26, retiring all three batters he faced.[5]
In 2012, Herrera appeared in 76 games and posted a 2.35 ERA over 84 innings while striking out 77. On August 30, 2012, Herrera recorded his first career save, against Detroit.[6] Herrera spent part of the 2013 season in the minors. Herrera finished the season with an ERA of 3.86 in 58+1⁄3 innings pitched, striking out 74 at a rate of 11.4 strikeouts per nine innings, still a career mark. Herrera also surrendered a career-high nine home runs.[7]
In 2014, Herrera became the go-to seventh inning option for manager Ned Yost. Along with set-up man Wade Davis and closer Greg Holland, Herrera was part of one of the most prolific late inning trios in all of baseball.[8] His ERA was 1.41, the best mark of his career, and he did not allow a home run during the entire regular season. He had his first professional at-bat in Game 3 of the World Series in San Francisco, when he struck out. He ended his first postseason with an aggregate 1.80 ERA, striking out 16 in 15 innings pitched.
During a game against the Oakland Athletics on April 19, 2015, Herrera was ejected for throwing a pitch behind Brett Lawrie.[9] One game prior to this incident, his teammate Yordano Ventura was also ejected for hitting Lawrie. On April 22, 2015, Herrera was suspended for five games.[10] Herrera appealed the suspension.[11] On April 25, 2015, Herrera was suspended an additional two games for his role in a brawl against the Chicago White Sox.[12] His four-seam fastball had the third-highest average speed of any MLB pitcher's pitches in 2015, at 98.4 mph.[13] Herrera, with the absence of Greg Holland in the 2015 postseason, became the eighth inning set-up man for the Royals. At the conclusion of the postseason, Herrera notched a 0.66 ERA with 22 strikeouts in 13+2⁄3 innings pitched with three holds.
Having spent the vast majority of his career as a seventh inning and eighth inning reliever, Herrera took over the role of the Kansas City Royals' closer following a sidelining injury to Wade Davis in 2016. Herrera collected 12 saves in 15 opportunities as closer. He ended his season with a 2.75 ERA, striking out 86 in 72 innings pitched surrendering a career low 12 walks in a season. Herrera was named to the 2016 MLB All-Star Game, his second consecutive trip to the Midsummer Classic. In 72 games, he had an ERA of 2.75 with 12 saves.[7]
After the trade of Wade Davis in 2017, Herrera was named the full-time closer for the Royals. He was 26-for-31 in save opportunities, ending the season with a career-high 4.25 ERA in 59+1⁄3 innings pitched.[7]
In 27 appearances for the 2018 Royals, Herrera compiled a 1.05 ERA with 14 saves, 22 strikeouts, and only two walks in 25+2⁄3 innings of work.[14]
Washington Nationals
On June 18, 2018, the Royals traded Herrera to the Washington Nationals in exchange for three minor-league players (third baseman Kelvin Gutiérrez, outfielder Blake Perkins, and right-handed pitcher Yohanse Morel).[14][15][16] With Washington he was 1–2 with three saves and a 4.34 ERA.[7] He became a free agent following the season.
Chicago White Sox
After he posted a combined 2.44 ERA for the Royals and the Nationals the previous season, the White Sox and Herrera agreed to a two-year deal on January 8, 2019. The contract carries an $8.5 million annual value and includes a club option worth $10 million for the 2021 season; it also includes a $1 million buyout.[17] His first season with the White Sox was disastrous, as he endured the worst season of his career. He was 3–3 with a 6.14 ERA in 57 games.
On July 31, 2020, Herrera was designated for assignment in order to make room for Nick Madrigal on the 40-man roster.[18] He was released on August 2.[19]
Chicago Cubs
On August 6, 2020, Herrera signed a minor league deal with the Chicago Cubs.[20] Herrera was released on August 26, 2020.[21]
Retirement
On February 26, 2021, Herrera announced his retirement from professional baseball via his Twitter account.[22][23]
Scouting report
With an overhand delivery and quick explosion from the stretch, Herrera throws hard like many Dominican pitchers; his two-seam fastball averages about 97 mph and tops out at 103. He pairs his fastball with a deceptive changeup around 87–88 and an occasional curveball in the mid-80s. Herrera occasionally throws a sinker to induce groundball outs. His slider is often touted as his best off-speed pitch.[24]
