- Bats Right, Throws Right
- Height 6' 0", Weight 195 lb.
- School Nippon Sport Science University
- High School Yamanashi Prefectural Tsuru High School
- Debut April 2, 2008
- Final Game May 7, 2009
- Born May 24, 1974 in Ōtsuki, Yamanashi Japan
Kobayashi played two years for Tokyo Gas in the industrial leagues after college. He was a first-round draft pick of the Chiba Lotte Marines in 1998. He debuted as a pro in 1999, going 5-5 with a 2.68 ERA in 46 games (7 starts). He allowed just 93 hits in 124 1/3 innings as one of the team's better hurlers.
In 2000, the right-hander was 11-6 with 14 saves and a 2.13 ERA in 65 outings. He was second to Shingo Ono on the staff in wins and was two saves behind team leader Brian Warren. His ERA was the best on the team. Had he qualified, he would have led the Pacific League in ERA by over a point. He made his first All-Star team.
Kobayashi went 0-4 with 33 saves and a 4.33 ERA in his first year exclusively as a closer, 2001. He again made the PL All-Star team. He was one save behind Pacific League leader Rodney Pedraza. In 2002, Kobayashi had a career year. He was 2-1 with 37 saves and a 0.83 ERA in 43 appearances that season. He allowed 26 hits in 43 1/3 innings. He walked six and striking out 41. He saved 33 games in a row to set a new Nippon Pro Baseball record. He again was one shy of the PL lead in saves, trailing Kiyoshi Toyoda. Surprisingly, he did not make the All-Star team that year.
The Ōtsuki native had another good campaign in 2003. He was 0-2 with 33 saves and a 2.87 ERA in 44 games. He again led his team in ERA and was second once more to Toyoda in saves in the Pacific League. He helped Japan win Gold at the 2003 Asian Championship.
Kobayashi's record in 2004 was 8-5 with 20 saves and a 3.90 ERA, finishing third in the PL in games saved. He allowed one run in three innings in the 2004 Olympics. He pitched one inning against Team Canada on August 20th, replacing Hitoki Iwase with a 9-0 lead in the 9th. He allowed a run on a Stubby Clapp double and Danny Klassen single and struck out two in the 9-1 win. On August 22nd, he relieved Daisuke Miura to protect a 6-1 lead in the 9th against the Greek national team and struck out the side in order. On August 25th, he again pitched the 9th inning against Canada, in a 11-2 win in the Bronze Medal game. He retired Pete LaForest, Rob Ducey and Adam Stern in order to end the game and give Japan the Bronze.
Kobayashi was 2-2 with 29 saves and a 2.58 ERA for the 2005 Marines. He won the PL Fireman of the Year Award and led the league in saves, 7 ahead of the runner-ups. He was second to Shunsuke Watanabe on the staff in ERA despite allowing over a hit per inning; he did walk just 9 in 45 1/3 innings. He made his third All-Star team. He reached 150 career saves in his 312th game, the fastest in NPB history that anyone had reached that mark. He pitched one scoreless inning in Game 4 of the 2005 Japan Series to finish up the sweep as Chiba Lotte won its first title ever.
The veteran reliever's record in 2006 was 6-2 with a 2.68 ERA and 34 saves. He walked just 8 in 53 2/3 IP. He was the third pitcher in NPB history to notch 200 career saves, following Kazuhiro Sasaki and Shingo Takatsu. He was 0.06 behind Yasuhiko Yabuta for the team lead in ERA and was second in the PL in saves behind Micheal Nakamura. Kobayashi made his 4th PL All-Star squad.
Kobayashi slumped to 2-7, 3.61 with 27 saves in 2007. He allowed over a hit per inning for the third time in his 9-year career. He still finished third in the Pacific League in saves. A free agent after the season, he signed with the Cleveland Indians.
He made his major league debut as a reliever on April 2, 2008. He replaced Fausto Carmona with a 6-1 lead in the 8th inning. Juan Uribe greeted him with a single. Kobayashi struck out Nick Swisher. Orlando Cabrera singled and Rafael Perez replaced Kobayashi to face Jim Thome. Kobayashi went 4-5 with 6 saves in 57 games for the Indians, with a 4.53 ERA (98 ERA+).
Kobayashi struggled with the Indians in 2009 (9 R in 9 2/3 IP) and was demoted the minors, where he was 2-2 with a save and a 4.66 ERA in 18 games for the Columbus Clippers, allowing 28 hits in 19 1/3 IP. He was then let go by Cleveland.
- 2008 Indians Media Guide
- Japan Baseball Daily by Gary Garland
- Defunct IBAF site
- Japanese Wikipedia entry