Leyson Séptimo

Leyson Séptimo Martinez (born July 7, 1985) is a Dominican former professional baseball pitcher. He played in Major League Baseball (MLB) for the Chicago White Sox and in Nippon Professional Baseball (NPB) for the Chunichi Dragons.

Playing career Arizona Diamondbacks On February 19, 2003, Séptimo signed with the Arizona Diamondbacks as an outfielder. He made his professional debut with the Low-A Yakima Bears, playing in 67 games and hitting .241 with two home runs and 21 RBI. Séptimo spent the 2006 campaign with the Single-A South Bend Silver Hawks, making 132 appearances and slashing .251/.310/.346 with six home runs, 51 RBI, and 10 stolen bases. In 2007, he played in 100 games for the High-A Visalia Rawhide, slashing .271/.322/.373 with five home runs, 42 RBI, and 12 stolen bases.

Séptimo converted into a pitcher in 2008, posting a 5.49 ERA in 27 games for Visalia. He split the 2009 campaign between Visalia and the Double-A Mobile BayBears, posting a combined 2-2 record and 4.92 ERA with 69 strikeouts and 9 saves across 45 appearances. Séptimo also appeared in the 2009 All-Star Futures Game. He was a Southern League mid-season All-Star in 2010. In 42 appearances split between Mobile and the Triple-A Reno Aces, Séptimo struggled to a 2-3 record and 6.75 ERA with 57 strikeouts across innings pitched. On October 14, Séptimo was removed from the 40-man roster and sent outright to the Triple-A Charlotte Knights.

Séptimo was promoted to the major leagues for the first time on June 28, 2012. The next day, Séptimo made his Major League debut against the New York Yankees, pitching a perfect 9th inning while striking out Alex Rodriguez and Robinson Canó.

On April 26, 2013, Séptimo was placed on the 60-day disabled list with a left shoulder strain. On June 11, he was activated from the disabled list. However, Séptimo was subsequently removed from the 40-man roster and sent outright to Triple-A Charlotte. He made 28 total appearances on the season, all with Charlotte, and accumulated a 4.42 ERA with 38 strikeouts. Séptimo elected free agency on October 1.

Southern Maryland Blue Crabs On February 10, 2014, Séptimo signed with the Lancaster Barnstormers of the Atlantic League of Professional Baseball. However, he was traded to the Southern Maryland Blue Crabs prior to the start of the season. In 8 appearances for the team, Séptimo struggled to a 14.85 ERA with 4 strikeouts across innings pitched.

York Revolution On January 10, 2015, Septimo signed a minor league contract with the Atlanta Braves organization. He was released by the Braves prior to the start of the season on March 30.

On April 26, 2015, Séptimo signed with the York Revolution of the Atlantic League of Professional Baseball. In 28 appearances for York, Séptimo posted a 2-2 record and 4.28 ERA with 26 strikeouts across innings pitched.

Amarillo Sox On July 11, 2015, Séptimo was traded to the Amarillo Sox of the American Association of Professional Baseball in exchange for cash considerations. In 11 appearances out of the bullpen, he struggled to a 1-4 record and 6.75 ERA with 8 strikeouts across innings pitched.

Joplin Blasters On August 10, 2015, Séptimo was traded to the Joplin Blasters of the American Association of Professional Baseball in exchange for future considerations. In 13 appearances down the stretch, Séptimo recorded an 0.98 ERA with 25 strikeouts across innings pitched.

Chunichi Dragons On June 5, 2016, Septimo signed with Chunichi Dragons of Nippon Professional Baseball. He appeared in three games for Chunichi, logging a 4.26 ERA with one strikeout across innings pitched. On October 29, it was confirmed that Septimo would be released from the Dragons along with Ricardo Nanita, Juan Jaime, Drew Naylor and Anderson Hernandez.

Coaching career On April 10, 2024, the Guerreros de Oaxaca of the Mexican League announced Séptimo as their bullpen coach. On July 6, 2025, Séptimo was fired by Oaxaca.

Pitching style Séptimo throws four pitches — a four-seam fastball in the mid-upper 90s, a two-seam fastball, a slider averaging at about 80 mph, and an occasional changeup. The slider is his main 2-strike pitch.