John Anthony Castino was born on October 23, 1954 in Evanston, ILlinois. He attended Rollins College at Winter Park, Florida getting picked by the Twins, third round in 1976. In the minors he was the AAA Southern Leagues All Star third baseman leading the league in fielding percentage.
He came up to the Twins in 1979 taking over as their third baseman winning the Rookie of the Year Award, tied in the voting with Alfredo Griffin. He played in 148 games but only had 393 at bats. He hit .285 with 112 hits 5 HRs 13 doubles 8 triples, 52 RBIs & a .331 on base percentage. He followed that up with career highs in HRs (16) RBIs (64) batting average (.302) & games (150).
In 1981 he led all AL third basemen in put outs (86) turning 24 double plays posting a .975 fielding percentage. He would play in over 100 games the next three seasons, but began to suffer from chronic back issues which ended his career by 1984. He never matched his first two seasons numbers, batting a best .277 in 1983, with 11 HRs & 57 RBIs when he switched over to being the teams main second baseman.
He finished his six year carrer after being released in October 1985, with a fused disc in his back. He played in 666 career games, batting .278 with 41 HRs 86 doubles & 249 RBIs.