Was signed by the Rangers as a non-drafted free agent, July 2, 2015...Was acquired by the Yankees for RHP Ronald Herrera, Nov. 20, 2017...Was acquired by the Reds, along with RHP Sonny Gray, for IF Shed Long and Cin's 2019 Competitive Balance A draft pick, Jan. 21, 2019...On Chattanooga's disabled list, July 30-Aug. 3, 2019.
2023
On 7/7 had "Tommy John" surgery to repair the torn ulnar collateral ligament in his left elbow...Made his last appearance for the Reds on 5/7 vs WSox...Two days later went on the 15-day injured list with a left elbow stress reaction...Was transferred to the 60-day injured list on 5/14, when RHP Silvino Bracho and RHP Alan Busenitz were promoted...Six times threw more than one inning, including a season-high two innings on 4/16 vs Phi...Retired the first batter in nine of his 14 apps...inherited 11 base runners, three scored...Once pitched on consecutive days (4/3-4/4 vs Cubs)...once in his career pitched on three consecutive days (8/5-8/7, 2022, all at Mil)...Pitched for Team Colombia in the 2023 World Baseball Classic (2g, 2ip, 4h, 1er, 1bb, 3k, 1hbp)...Pitched the seventh inning of Colombia's 10-inning, 5-4 win vs Mexico in Arizona Pool C (0.1ip, 2h, 1er, 0bb, 0k, 9 pitches)...didn't allow a run while pitching in the fourth and fifth innings of the 5-0 loss vs Canada (1.2ip, 2h, 1bb, 3k, 25 pitches)...On 11/17 was non-tendered...10 days later was re-signed by the Reds to a Minor League contract and invited to 2024 Major League Spring Training camp.
2022
Went 0-4, 19.85 in 4 starts and 4-0, 2.96 in 41 relief appearances...In 40 appearances during his second stint with the Reds, all in relief beginning 6/13, posted a 3.32 ERA...Began the season on the Opening Day roster as a member of the Reds' rotation...made all four of his starts in his first five appearances...In his season debut, on 4/8 at Atl in the season's second game, was trying to become the first lefthanded pitcher in Reds history ever to begin his Major League career with 3 starts in which he recorded at least 5.0 innings while allowing one or fewer runs... finished the 7-6 loss with five earned runs allowed in 2.1 innings...With the loss in his season debut, also was denied in his bid to become the first Reds lefthanded pitcher to win each of his first three Major League starts since Noodles Hahn in 1899 and the first Reds lefthander to win each of first three career appearances, all starts, since Bill Dammann in 1897...RHP Wayne Simpson, from 4/9-4/19, 1970, remains the last Reds pitcher to win each of his first three Major League appearances, all starts...Was scheduled to make his second appearance and start on 4/14 at LAD...following the game on 4/13 at LAD, RHP Luis Cessa was named the next day's starter in Sanmartin's slot...after Cessa allowed three runs in the first inning of that 9-4 loss, Sanmartin entered in the second and threw 5.0 scoreless innings...In five appearances, including four starts, went 0-4, 13.78 before he was optioned to Louisville on 5/1, when the 28-player roster dropped to 26...Before that 5/1 option, 17 of his last 20 batters reached base safely and 15 scored...After posting a 7.36 ERA in two starts and five relief appearances for Louisville, prior to the game on 6/12 at StL was added to the Taxi Squad...before the next night's game at Ari was added to the active roster and remained with the Reds the rest of the season...Retired the first batter in 28 of his 41 relief appearances...stranded 17 of 26 inherited runners...11 times threw more than 1.0 inning in relief and 6 times threw at least 2.0 innings...threw a season-high 5.0 innings out of the bullpen on 4/14 at LAD after starter Luis Cessa pitched 1.0 inning...Six times pitched on consecutive days (last, 9/20 & 9/21 vs Bos)...from 8/5-8/7 at American Family Field pitched three days in a row for the first time in his career...was one of only two Reds pitchers to pitch on three consecutive days (Hunter Strickland, 9/11-9/13)...From 7/7-7/14, in each of his three consecutive appearances earned the win (3-0, 1.93, 4.2ip, 1h, 1er, 2bb, 3k, 1hr, .067baa)...From 7/12-7/22 was the winning pitcher in each of three straight Reds victories... became the first Reds pitcher to earn the decision in three consecutive team wins since Dan Straily did it in September 2016...In the 11-4 loss on 8/16 vs Phi allowed seven hits, five runs and two home runs, all career highs for a relief appearance...snapped an 11-game streak in which he had not allowed an earned run (7ip, 9h, 1r, 3bb, 6k)...his ERA as a reliever jumped from 1.01 to 2.57.
2021
Was an MiLB.com Organization All-Star...Was promoted for the last six games of the season and made his first two Major League apps...Made his Major League debut in the 13-1 makeup game win on 9/27 vs Pit (5.2ip, 1r)...started in place of veteran LHP Wade Miley, who went on the 10-day injured list with a neck strain...Became the first Reds pitcher to win his Major League debut and the first Reds pitcher to win in his first career start since LHP Amir Garrett did both on 4/7/2017 at StL (2-0)...The next day, on 9/28 at WSox, starter RHP Riley O’Brien made his first career appearance in a 7-1 loss...Sanmartin and O’Brien became only the fourth set of Reds starting pitchers since 1900 to make Major League debuts in consecutive games, joining RHP Rookie Davis & LHP Amir Garrett in 2017 (4/6 vs Phi, 4/7 at StL), Eddie Erautt & Bud Lively in 1947 (4/16, 4/17) and Martin Glendon & Bob Ewing in 1902 (4/18, 4/19)...In his second appearance, earned the 6-3 win at Pit in the final game of the championship season (6ip, 1r)...Became the first Reds pitcher to win each of his first 2 career starts and the first to throw at least 5.0 innings in each of his first two starts since LHP Amir Garrett did both in 2017, on 4/17 at StL (6ip, 0r) & 4/12 at Pit (6.2ip, 2r)...Was the eighth of nine Reds players to make Major League debuts in 2021 (2B Jonathan India, RHP Ryan Hendrix, RHP Vladimir Gutierrez, RHP Tony Santillan, IF Alejo Lopez, OF TJ Friedl, RHP Dauri Moreta, RHP Riley O’Brien)...Became the 54th player and 16th rookie to appear in a game for the Reds in 2021...the night after his debut, on 9/28 at WSox, RHP Riley O’Brien became the 55th player and 17th rookie...the club record for players used in a season is 57 (2003)...Spent the 2021 minor league season at Class AA Chattanooga and Class AAA Louisville, where in 17 starts and eight relief apps he combined to finish 10-2, 3.32...Began the season at Chattanooga and went 2-0, 0.53 in three starts and one relief appearance...in his last two starts and 11.0 innings for the Lookouts recorded two walks and 17 strikeouts...On 5/26 was promoted to Louisville, his first action above Class AA, and finished his minor league season with the Bats...At the time of his promotion to Louisville ranked second in Class AA in opponents’ batting average (.133) and WHIP (0.72) and third in ERA (0.50)...Finished his minor league season with 112 strikeouts (100.1ip), just two shy of his minor league single-season high (114, 2019)...Produced at least 100 strikeouts for the second consecutive season (2019, 2021)...Was one of 18 players invited to early minor league spring training camp...posted a 3.86 ERA in three exhibition "A" games for the Reds...wore uniform #94...Following the season played for Estrellas de Oriente in the Dominican Winter League (7gs, 0-2, 1.45, 31ip, 16h, 11bb, 19k, 0hr, .154baa).
2020
Was not on the Reds' 60-player pool Summer Camp roster...In the 2020-21 Caribbean Series posted 1.80 ERA with eight strikeouts in 5.0 innings for Colombia.
