Has many hobbies outside of baseball...Loves to draw and designs custom shoes (@kix\_by\_yama on Instagram)...Also enjoys clay sculpting and DIY home improvements...Is passionate about hair cutting...He has served as the team barber for his minor league clubs and during his Arizona Fall League stint in 2018...You can see some of his cuts on Instagram at @cutz\_by\_yama...Is a graduate of the Saint Louis School in Honolulu, Hawaii...Other notable athletic alumni from that high school include former New York Met Benny Agbayani and 2011 AL All-Star Brandon League as well as Heisman winners and current NFL quarterbacks Tua Tagovailoa and Marcus Mariota.
Made four appearances (three starts) and allowed at least three runs in each outing...Allowed a career-high 11 hits, 13 runs (12 earned) and four home runs in his last appearance of the year, Sept. 9 at Atlanta, in a 29-9 Marlins loss.
Made his Major League debut in June 2019 and recorded one of the best starts to a career in Club history...His average against (.191) ranked third in the Majors (min. 15 starts), behind Houston's Justin Verlander (.172) and Gerrit Cole (.186), and was the second-lowest mark in Franchise history (min. 15 starts), behind José Fernandez in 2013 (.182)...He allowed four-or-fewer hits in 11 of his 15 outings, a pace of just 6.18 hits per nine, which ranked third in the Majors (min. 15 starts), behind Verlander (5.53) and Cole (6.02)...He was recalled from Double-A Jacksonville on June 12 and made his MLB debut that night vs. St. Louis. He tossed 7.0 shutout innings, scattering three hits and two walks, with five strikeouts, in a 9-0 victory...His 7.0 innings tied a club record for innings pitched in an MLB debut (Dillon Peters, Brad Penny, and Justin Nicolino); his three hits were tied for the fewest allowed in a start (Peters); and it was only the third scoreless debut (Peters and Nicolino)...He followed that up with another 7.0 scoreless innings, also against the Cardinals, this time on June 18 in St. Louis (6-0 win). According to the Elias Sports Bureau, he became just the second pitcher since 1893 (when the current mound distance was established) whose first two career outings were scoreless starts against the same opponent; the other was Atlanta's Larry McWilliams, who did so vs. the Mets on July 17 (7.0 ip) and July 23 (6.0 ip) in 1978...His 14.0 consecutive scoreless innings to begin his MLB career set a Franchise record by a starter, surpassing a 10.0 inning run by Josh Beckett in 2001. - Elias Sports Bureau...On June 23 at Philadelphia, won his third consecutive appearance to open his career, becoming the first pitcher in Club history to do so. He was just the second pitcher in the Modern Era (since 1900) to win each of his first three career starts and allow seven-or-fewer hits, joining Cincinnati's Wayne Simpson in 1970 (7 hits in 25.0 ip) - Elias Sports Bureau...Yamamoto and San Diego's Chris Paddack (also 2019) both opened their careers with five straight starts allowing three-or-fewer hits, the only pitchers since 1900 to do so. St. Louis's Tom Cheney (1957-'59) did not allow more than three hits over his first five career starts, and the Angels' Cory Rasmus (2014-'15) had a seven-start streak, but those were not their five career appearances. - Elias Sports Bureau...Yamamoto allowed four-or-fewer hits in each of his first eight starts of his career. According to the Elias Sports Bureau, he was the only starting pitcher since 1893 to allow four-or-fewer hits in his first eight career starts (excluding openers)...Picked up his fourth win in his sixth start, and was 4-0 with a 1.59 ERA (34.0/6) at that point. Over his next seven starts, went 0-5, 8.13 (34.1/31). However, opponents batted just .241 against him during the skid...He gave up his first home run in the first inning of his seventh start, which was also his first loss, on July 21 at the Dodgers. He became just the fourth pitcher in Club history to make six-plus starts without a home run allowed to open his career, joining Kevin Olsen (7 starts/40.1 ip from 2001-'02), Jason Vargas (6/38.1 in 2005), and Josh Johnson (6/37.0 from 2005-'06)...After the seventh start of that stretch, was placed on the Injured List (right forearm strain) and missed 25 games. Returned on September 21 and made two starts. Did not factor in the decision in either outings (team was 1-1), but posted a 1.74 ERA (10.1/2) and allowed just seven hits combined (.189 average against)...He was tied for 10th in strikeouts in the Southern League when promoted to Miami.
Combined to go 6-1 with a 1.83 ERA (68.2/14 er) over 13 starts for the GCL Marlins (rehab), High-A Jupiter and Double-A Jacksonville...Had 85 strikeouts and 14 walks in 68.2 innings, finishing with a 6.1 strikeout/walk ratio...In seven starts for Jupiter, posted 4-1 mark with 1.55 ERA (40.2/7)...Went 4-0 with a 1.32 ERA (34.2/5) over first six starts of the season with Hammerheads. Totaled 35 strikeouts and just seven walks during that stretch...Had a 14.0 inning scoreless innings streak over two starts from June 20-26. Allowed six hits and one walk with 15 strikeouts during that span...Named Florida State League Pitcher of the Week (June 18-24) after recording a career-high 13 strikeouts over 7.0 shutout innings vs. Florida on June 20...Had a 12 strikeout performance two starts later on July 2 vs. Florida...Made first career Double-A start on July 9 with Jacksonville. Surrendered just two runs and one walk over 7.0 innings...Made six starts for Salt River Rafters in Arizona Fall League, going 3-0 with a 2.08 ERA (26.0 ip/6 er)...Finished tied for second in the AFL in wins, tied for fourth in strikeouts (27) and innings pitched, fifth in WHIP (1.08), and sixth in ERA. Among starting pitchers, held opponents to lowest batting average (.172)...Started the AFL Championship Game against Peoria and tossed 4.0 shutout innings, allowing two hits and five walks, while striking out six. Peoria rallied for two runs in bottom of the ninth and won game, 3-2, in the 10th.
Was 1-7 with a 6.99 ERA (83.2 ip/65 er) in first two professional seasons; in last two seasons, is 16-12 with 3.23 ERA (245.1/88)...Spent entire 2017 campaign with Single-A Carolina, posting career-high nine wins and career-low 2.51 ERA (111.0/31)...Led Mudcats and ranked tied for fourth in Brewers' farm system in wins...Was on 7-Day disabled list from April 13-May 11 with a right shoulder strain. ..Went 1-0 with one save and a 4.50 ERA (12.0/6) in four relief outings, and 8-4, 2.27 (99.0/25) in 18 starts...Save came in 3.0-inning outing on May 22 at Winston-Salem...Last 11 appearances of season were starts; factored in decision in 10 of those outings (7-3)...Won three straight starts from July 24-August 4; suffered a loss on Aug. 10; won four straight starts to end season, beginning Aug. 16...Had back-to-back complete games on July 24 & 29, both wins...On July 24 at Myrtle Beach, tossed 5.0-inning complete game, allowing three runs on five hits, with three strikeouts...On July 29 vs. Wilmington, tossed 7.0-inning shutout, allowing four hits and three walks, with seven strikeouts...Was named Carolina League Pitcher of the Week for Aug. 28-September 4 after going 2-0 with a 0.00 ERA (14.0 ip, 0 er) with two walks and 14 strikeouts ...Opponents hit .206 (21x102) with runners in scoring position.