Maldonado was drafted by the Anaheim Angels in the 27th round of the 2004 Major League Baseball draft. He played his first professional season for the rookie-level Arizona League Angels that season, and batted.217/.277/.233. In 2005, he again played for Arizona and the rookie-level Orem Owlz. After he played one more season for the Arizona Angels in 2006, in which he batted.222/.329/.270, he was released.
Milwaukee Brewers
In 2007, Maldonado signed a minor league contract with the Milwaukee Brewers and played for the West Virginia Power of the Class ASouth Atlantic League, and batted.221/.309/.288. He played for the Brevard County Manatees of the Class A-AdvancedFlorida State League and the Huntsville Stars of the Class AASouthern League in 2008. He began the 2009 season with the Manatees, but was called up to the Nashville Sounds of the Class AAAPacific Coast League at mid-season. However, he returned to the Manatees to finish out the 2009 season. In 2009 he batted a combined.201/.295/.257. Maldonado played the majority of 2010 with Nashville, but also spent time with Huntsville and Brevard County. He made his Major League debut on September 3, 2011 and played in 3 games for the Brewers after his callup, striking out in his only at bat. Maldonado was called up to the Brewers yet again in May 2012 when starting catcher Jonathan Lucroy went down with a freak hand injury due to his wife dropping a suitcase on it. In 2012 with Nashville he batted.198/.270/.347. He played 78 games for the Brewers in 2012. He remained in the majors for the 2013 season. In 2013 he batted.169/.236/.284 for the Brewers. Maldonado was involved in an unusual play in which he hit the cover off the baseball. In a game against the Pittsburgh Pirates on April 18, 2014, Maldonado hit a ground ball to third base. However, by the time Pirates third baseman Pedro Álvarez fielded the ball, the cover had partially come off the baseball and was hanging off the side; Alvarez threw the ball to first anyway but the ball fell apart in midair, made it to first on several hops, and Maldonado was awarded an infield hit. Two days later he punched Travis Snider in the face in Pittsburgh, and was suspended for five games and fined $2,500. On May 31, 2015, Maldonado caught a 17-inning game and also hit a walk-off home run in the bottom of the 17th against the Arizona Diamondbacks, his first career walk-off home run. In 2015 he batted.210/.282/.293. In 2016 he batted.202/.332/.351 for the Brewers.
Second Stint with Angels
On December 13, 2016, Maldonado and Drew Gagnon were traded to the Los Angeles Angels for Jett Bandy. Maldonado was named the starting catcher and played in a career high 138 games, batting.221 with 14 home runs and 38 RBIs. He won a Rawlings Gold Glove Award after the 2017 season.
Houston Astros
On July 26, 2018, the Angels traded Maldonado to the Houston Astros in exchange for pitcher prospect Patrick Sandoval and international pool space cash. He became a free agent on October 29.
Kansas City Royals
The Kansas City Royals signed Maldonado to a one-year, $2.5 million contract on March 11, 2019, following an injury to Salvador Pérez. He batted.227/.291/.366 for the Royals.
Chicago Cubs
On July 15, the Royals traded Maldonado to the Chicago Cubs in exchange for left-handed pitcher Mike Montgomery. He had 11 at bats with the Cubs, in which he failed to get a hit.
Second stint with the Houston Astros
On July 31, 2019, the Cubs traded Maldonado to the Houston Astros in exchange for outfielder Tony Kemp. He batted.202 for Houston. On defense, he threw out one of 11 attempted base-stealers for the Astros. Maldonado was Gerrit Cole's personal catcher during this stint. Over 10 starts with Maldonado behind the plate Cole pitched to a 1.57 ERA. On December 23, 2019, Maldonado signed a 2-year contract with the Astros, worth $7 million..
