Mackanin was drafted by the Washington Senators in the 1969 Major League Baseball Draft and made his debut with them in 1973, after they moved and became the Texas Rangers. Following his trade to the Montreal Expos, he also played for the Philadelphia Phillies and Minnesota Twins. Mackanin's best season offensively was in 1975, when he posted a.225 batting average, along with 12 home runs, and 44 runs batted in.
Career statistics
In a nine-year big league career, Mackanin’s career statistics include 548 games played, 355 hits, 1,570 at bats, a.226 career batting average, 30 home runs, 141 RBI, and an on-base percentage of.263. He ended his career with a.968 fielding percentage.
Managerial career
Early career
After retiring as a player, Mackanin spent many years managing and coaching in the minor leagues. He became the Expos' third base coach in 1997 and spent four years in that position. After managing the minor leagueHickory Crawdads and Lynchburg Hillcatsin 2001 and 2002, Mackanin became the bench coach for the Pittsburgh Pirates for the 2003 season. After Lloyd McClendon was fired, Mackanin served as the Pirates' interim manager for the last month of 2005, leading the team to a 12–14 record. He spent the next season managing in the Pirates' minor league system at Bradenton. Mackanin was hired by the Cincinnati Reds as a scout for the 2007 season, but when the team fired manager Jerry Narron on July 1 of that year, he was named the club's interim manager. Narron had led the Reds in the first half of the 2007 season to a league-worst 51 losses, but during Mackanin's tenure, the team had a winning percentage above.500. The Reds decided not to hire Mackanin on permanently for the 2008 campaign, instead deciding on veteran experience with Dusty Baker. Mackanin was hired by the Philadelphia Phillies in 2009 as the bench coach. On October 3, 2012, the Phillies fired him by deciding not to renew his contract for the 2013 season. He was rehired by the Phillies for the 2014 season to be the 3rd base coach for Ryne Sandberg. On June 26, 2015, Mackanin was appointed Phillies manager after Sandberg suddenly stepped down. In 2015 Mackanin was successful on a lower percentage of replay challenges than any other MLB manager with 10 or more challenges, at 76.2%. On September 29, 2017, the Phillies announced that Mackanin would not return for the 2018 season, but would instead take on a front office role for the remainder of his contract.