The St. Louis Cardinals and JJ Wetherholt have agreed to an eight-year, $112.5 million contract that starts next season and buys out the rookie second baseman's first several years of potential free agency.

St. Louis selected Wetherholt seventh overall out of West Virginia in the 2024 amateur draft, and he rocketed through their farm system. The 23-year-old who played for the Mars Fightin’ Planets in high school made his major league debut on opening day and was hitting .267 with 13 homers and 36 RBIs and nine stolen bases going into Friday night's game against the Atlanta Braves.

Advanced metrics also have graded Wetherholt as one of the best defensive second basemen in baseball this season.

St. Louis Cardinals rookie second baseman JJ Wetherholt, right, is greeted by Nelson Velázquez, left, after hitting a home run against the Chicago Cubs during the first inning of Saturday’s baseball game in Chicago. Associated Press

He is earning the major league minimum $780,000 this year.

Wetherholt's emergence in the middle of the St. Louis infield is a big reason the club has been one of the surprises of the first half of the season. The Cardinals were 48-44 and three games out of an National League wild-card spot heading into the weekend.

His deal is one of the first big signings for St. Louis since significant changes were made to the top of the organizational ladder.

Chaim Bloom took over as the Cardinals' president of baseball operations in September, replacing longtime general manager John Mozeliak. Then last month, Bill DeWitt III took over as chief executive officer, though Bill DeWitt Jr. has continued as its chairman and principal owner with a hand in baseball and business matters.