Cubs working on extension for Starlin Castro

The Cubs are progressing toward a long-term contract extension with shortstop Starlin Castro, according to multiple reports.

CSNChicago.com was first to report on the club's conversations with the two-time All-Star. Castro's agent, Paul Kinzer, told the website that "Starlin loves being a Chicago Cub and would like to play there his entire career. ... We have been talking about a long-term deal."

Castro cannot become a free agent until after the 2016 season. The Cubs would be buying out his remaining arbitration years and at least two years of free agency, should the extension be for six or more years, as CSNChicago.com reported.

In his third season with Chicago, the 22-year-old is batting .276 with 12 home runs, 58 RBIs and 19 stolen bases. He led the National League with 207 hits last season, when he batted .307.

The native of the Dominican Republic signed with the Cubs as an amateur free agent in 2006.