ST. LOUIS -- Three-time All-Star infielder Matt Carpenter and the St. Louis Cardinals have agreed to a contract that adds $37 million in guaranteed money for 2020 and '21, a deal that includes an option for 2022.

The 33-year-old has a $14.5 million salary this season as part of a $52 million, six-year deal that included an $18.5 million club option for 2020 with a $2 million buyout.

Under the new deal, he has guaranteed salaries of $18.5 million in both 2020 and '21. The 2022 salary would become guaranteed if he has 1,100 plate appearances combined in 2020 and '21, including at least 550 in '21.

"It's really very humbling," Carpenter said after Wednesday's announcement. "To be able to potentially be here for an entire career is something that I don't take for granted. Every day it's something that I try to live up to."

He has a .273 batting average with 134 home runs and a .376 on base percentage in 1,031 games since debuting in 2011 with the Cardinals. Carpenter was an All-Star in 2013, 2014, and 2016. He finished among the top 10 in MVP voting in 2013 and last year.

"He's created enormous flexibility for the Cardinals because he was always willing to play a different position to allow us to maximize our team," Cardinals president of baseball operations John Mozeliak said. "Really what it says is he's truly a team player. So, the reason we're motivated to try to do this is where he's at in his career, we wanted him to continue to wear the Cardinal uniform."

Carpenter was a 13th-round draft pick by the Cardinals in 2009. He became the fourth St. Louis player since February to sign a long-term deal after first baseman Paul Goldschmidt, pitcher Miles Mikolas, and first baseman/outfielder Jose Martinez.

"When we get a core player, we like to keep him here," Cardinals chairman Bill DeWitt Jr. said. "We've made every effort to do that since I've been here and before."