- Bats Right, Throws Right
- Height 6' 2", Weight 210 lb.
- High School Minoshima High School
- Debut April 5, 1998
- Final Game September 11, 2002
- Born April 20, 1965 in Arita-gun, Wakayama, Japan
Masato Yoshii was drafted by the Kintetsu Buffaloes in the second round of the 1984 draft. Yoshii reached the Buffaloes ichi-gun(top team) in 1985, pitching in two games. He had ERAs over 20 in limited duty in 1985-1986 and did not see regular duty until 1988, when he went 10-2 with 24 saves and a 2.69 ERA in 50 games and as a result was named the Fireman of the Year. He was one save behind Pacific League leader Kazuhiko Ushijima.
His success continued in the 1989 season, where he went 5-5 with 20 saves and a 2.99 ERA in 47 games. During the 1990 season, Yoshii was 8-9 with 15 saves and a 3.39 ERA in 45 games. In Masato's next two years he appeared in only 30 games.
Yoshii joined the Buffaloes rotation in 1993, going 5-5 with a 2.67 ERA in 22 games. He struggled in 1994 with a record of 7-7 and a 5.47 ERA in 21 games. In 1995 Yoshii joined the Yakult Swallows, posting 10 wins and seven losses with a 3.12 ERA in 25 games. He again had a 10-7 record in 1996 with a 3.24 ERA in 25 games, the third-best ERA in the Central League. During Yoshii's final year with the Swallows he had a career year in terms of wins, going 13-6 with a 2.99 ERA in 28 games. He teamed with Kazuya Yabuta (15-5, 2.96) and Kazuhisa Ishii (10-4, 1.91) to lead Yakult to the Japan Series. He was third in the Central League in wins that year, behind Masahiro Yamamoto (18) and Yabuta.
In 1998 he became a free agent. He initially had wanted to stay with Yakult but was pressured to leave by agent Don Nomura, who claimed he would be standing up for his rights and showing an example for the next generation. Nomura denied that team loyalty should play a role. When Yakult refused to extend Masato's contract by two years, he began fielding extravagant offers from the Seibu Lions and Hanshin Tigers ($5 million over 4 years), Yokohama BayStars ($7 million) and Yomiuri Giants ($9 million). Yoshii was interested in joining Yomiuri but Nomura kept on encouraging greed, saying he should ask for another $4 million and cut back on his workout. Manager Shigeo Nagashima agreed but the Giants' general manager refused, which was a rational response given that Yoshii was already demanding more in salary than he was probably worth.
Former teammate Hideo Nomo convinced Yoshii to look into joining an American team. Yoshii responded by refusing all the million-dollar offers to sign with the New York Mets for $200,000 with performance bonuses that would push his salary over one million dollars in his first year.
In his rookie year with the Mets, he went 6-8 with a 3.93 ERA (a 107 ERA+) in 29 games. After signing a two-year extension for over $5 million, Yoshii declined in 1999, as his ERA rose to 4.40 (ERA+ of 100) but he got more offensive support and went 12-8 in 31 games. In January 2000 he was traded to the Colorado Rockies for pitchers Bobby Jones and Lariel Gonzalez. In his only year with the Rockies he went 6-15 with a 5.86 ERA in 29 games. He was sixth in the National League in losses but his ERA+ was still just fine, 101.
As a result of poor analysis of the effect of Coors Field on pitchers, Yoshii was released by the Rockies in March 2001 and was signed by the Montreal Expos. Masato went 4-7 with a 4.78 ERA in 42 games that year, mostly out of the bullpen. In Yoshii's final year in the majors, he went 4-9 with a 4.11 ERA in 31 games. His ERA+ never fell below 97 in the majors and was 101 for his career. His record was less flattering (32-47). Yoshii had shown that even a non-star from Japan could achieve success in Major League Baseball.
At age 38, there were few MLB teams interested and Yoshii was signed by the Orix Blue Wave in 2003. He struggled badly, going 2-7 with a 6.51 ERA in 24 games. During the 2004 season he spent most of the year with the Surpass Kobe, Orix's ni-gun team and only appeared in three games with Orix. Yoshii experienced a recovery, with a line of 6-5 with a 4.03 ERA in 15 games with the newly-merged Orix Buffaloes in 2005. After Jeremy Powell and Hidetaka Kawagoe, he was the club's most reliable starter, even at age 40. The old-timer remained fairly effective in 2006, going 7-9 with a 3.81 ERA and only 22 walks in 101 2/3 IP. He even made his fifth All-Star team.
Yoshii began 2007 with a 1-6, 5.75 record, then was traded in late June to the Chiba Lotte Marines for backup OF Koji Hirashita. He was 0-3 with a 13.14 ERA for the Marines, allowing 30 hits in 12 1/3 IP. Yoshii called it quits after that season, signing on as Nippon Ham's pitching coach.
Yoshii was 89-82 with 62 saves and a 3.86 ERA in 385 games in Nippon Pro Baseball in his career.