Starlin Castro could be in a Cubs uniform through at least the 2020 season. (Getty Images)

The Cubs have agreed to terms with shortstop Starlin Castro on a seven-year, $60-million contract extension, Enrique Rojas of ESPN Deportes reports and CBSSports.com Insider Jon Heyman confirms.

Heyman also reports that the deal includes a $16-million option/$1-million buyout for 2020, with the $1-million buyout counting toward the guaranteed $60 million. The option means that Castro could be under contract through his age-30 season.  

This year, the 22-year-old two-time All-Star is batting .278/.309/.423 with 12 homers and 19 stolen bases. He's a career .297/.333/.422 hitter.

While Castro needs time to develop with the glove and is prone to mental lapses, the Cubs understandably see him as a franchise cornerstone. After all, shortstops who reach the majors for good at age 20 and provide above-average production don't come along too often.  

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