The six foot right handed hitter, batted .305 at A ball & played a solid infield. He made it to the big leagues as the Indians starting shortstop in 1970. He got a hit in his first MLB at bat, but only batted .211 on the season.
He posted a .961 fielding % making 23 errors at short stop (2nd in the AL) turning 79 double plays. He led the league in sac flies (10) hitting 14 doubles with 37 RBIs. He hit 6 HRs & was the only starting Indian not to hit 10 HRs.
In 1971 he improved to the fourth highest fielding percentage at shortstop (.977) but his season was cut short when he suffered a concussion.
In a game against the White Sox, future Mets coach Tom McGraw hit a pop fly to shallow left field. Heidemann, Vada Pinson and John Lowenstein all went for the ball, colliding in the outfield. The ball rolled away & McCraw had himself an inside the park HR.
By 1972 Heidemann lost his starting job to Frank Duffy. He was traded to the World Champion Oakland A’s, along with Ray Fosse in exchange for Dave Duncan & George Hendrick. He never played in the big leagues for Oakland, spending the 1973 season at AAA Tucson, batting .283.
He eventually had his contract sold back to the Cleveland Indians.
In 1974 after batting .091 in 12 games he was traded to the St. Louis Cardinals for Luis Alvarado and Ed Crosby. There he hit a career best .271 in 47 games, but at the end of the year was traded to the New York Mets along with Mike Vail for shortstop Teddy Martinez.
Mets Career: Heidemann had a short career with the Mets, mostly backing up shortstops Bud Harrelson & Mike Phillips in parts of the 1975 &1976 seasons. He would also play some third & second base as well. Heidemann had a good glove but hit little, with no power.
In his third game with the Mets he had the biggest day of his career, which fittingly came against his old St. Louis Cardinal teammates in a 14-7 Mets win on April 17th 1975.
In his first at bat, he drew a bases loaded walk, then scored on a Jerry Koosman base hit, in the Mets six run first inning. He later hit a bases loaded double, scoring Rusty Staub, John Milner & Wayne Garrett, giving him a four RBI day.
Three days later he hit his only Mets career HR, which was also his first HR since 1970.
It came on April 20th, in an 8-6 Mets win at Shea Stadium against the Chicago Cubs. On July 20th, he tripled off the Astros Dave Roberts, bringing home two runs in a 10-9 Mets win at Shea.
In August he had another two RBI day in a 4-3 Mets loss to the Los Angeles Dodgers. In early September, he drove in runs in three straight games, having a three hit day in Pittsburgh, on September 11th in a 7-0 Jerry Koosman shut out. Overall in 61 games, for the '75 third place Mets, he would hit .214 for the Mets with one HR, four doubles & 16 RBIs.
He began the 1976 bicentennial year, at AAA Tidewater, hitting .356 there getting a call up that June. After only five games he was batting .083 and the Mets traded him to the Milwaukee Brewers for minor leaguer Tom Deidel. Heidemann played behind veteran Don Money at third, & 21 year old shortstop Robin Yount at short.
In 1976 he hit his final HR of his career off the Red Sox Bill Lee. Heidemann finished his MLB playing career in Milwaukee in 1977. In 1978 he went to the Seattle Mariners organization playing in the minors there for two years.
In his eight season career Heidemann hit .211 with 231 hits, 9 HRs 27 doubles 4 triples a .254 on base % & 75 RBIs.
On the field he posted a .965 fielding %, making 42 errors in 1199 chances. He played 322 games at short, 51 games at third, 28 at second & one game at first base.
Family: Jack married his first wife Carol & they have four children.
Retirement: After baseball he retired to Tempe, Arizona. There he was a licensed real estate agent for over thirty years before retiring. He is part of the MLB Arizona alumni & still speaks & coaches at baseball events.