- Bats Right, Throws Left
- Height 5' 8", Weight 143 lb.
Kozo Naito played for 14 years in Nippon Pro Baseball as a P/1B/OF, setting several records, and later became an umpire.
Naito pitched for Tokyo Legal in the Japanese industrial leagues. He struck out 26 batters in a perfect game in the finals one year. When the Japanese Professional Baseball League was formed, Naito was a logical choice to turn pro. Signing with the Nagoya Golden Dolphins, he went 1-1 with a 3.60 ERA in the spring of 1936 and walked 22 in 29 2/3 IP. In the fall campaign, his record was 6-8 with a 3.63 ERA and hit .259/.348/.345. He walked 103 and struck out 139 in 133 2/3 IP. He led the JPBL in games pitcher (24), innings, batters faced (602), homers allowed (4), strikeouts, walks, hit batters (8), wild pitches (7), runs allowed (88) and earned runs allowed (54). His K/9 ratio for the total year was a NPB record until Masaichi Kaneda finally broke it 22 years later. He was then drafted into the military and served two years.
Moving on to the Asahi club for 1941, Kozo's record was 0-1 with a 8.18 ERA and walked 15 in 10 2/3 IP. He was just 5 for 28 at the plate as well. The next year, he had a 5-10, 1.52 record. He walked 112 in 153 1/3 innings but allowed just 80 hits. He hit .215/.301/.262. In 1943, he was 8-12 with a 2.25 ERA; his control improved significantly (105 BB in 109 2/3 IP). He batted .194/.235/.280.
Naito finally reached .500 for the only time in 1944 (11-11) with a 2.10 ERA. He walked 136 in 222 1/3 IP, leading the league. He also led in runs (78) and earned runs allowed (52). He hit .174/.224/.229. The JPBL season was cancelled the next season due to World War II.
In 1946, Naito was with the Goldstar club. He pitched in 57 games, going 19-25 with a 2.90 ERA and was 8th in the JPBL in ERA. He hit .253/.286/.276. On July 15, the southpaw allowed a record 12 runs in an inning.
Kozo's 1947 season produced a 12-14, 2.86 record for the Kinsei Stars and had his best year at the plate, batting .312/.372/.376; had he qualified, he would have been second in the JPBL in average. In 1948, Naito was 7-11 with a 2.68 ERA and only walked 37 in 160 2/3 IP as his control had improved significantly. He hit .226/.262/.258.
In 1949, Kozo was on the Hankyu Braves staff, posting a 7-14, 4.83 line. He joined the new Hiroshima Carp in 1950 and got the first win in franchise history on March 14. He was 11-19 with a 5.52 ERA for the expansion team, allowing 276 hits in 216 1/3 innings, allowing 23 homers. Naito's final season was 1951 with a 1-4, 6.30 mark.
Overall, Naito had gone 92-141 with a 3.27 ERA. He walked 1,108 and fanned 1,031 in 2,220 2/3 IP and allowed 1,974 hits in 368 games. He hit .221/.278/.273.
After retiring, he umpired in the Central League.
For a picture of Naito, see This page from the Chugoku Shimbun