The Rangers and Adrian Beltre have agreed to a two-year contract extension worth $18 million per year, according to MLB.com.

Beltre, 37, was set to become a free agent at the end of this season, when the six-year contract he signed in January 2011 expires.

"We would like Adrian to finish his career as a Ranger," general manager Jon Daniels said last year.

The Giants have locked up another key homegrown player.

Giants first baseman Brandon Belt agreed to terms on a five-year extension Friday, per multiple sources. The deal also reworks Belt’s current one-year deal, locking him up for six total seasons. Financial details were not immediately available, but per sources, Belt’s deal is similar to but bigger than Brandon Crawford’s six-year $75 million deal.

Gregory Polanco and the Pirates agreed on a five-year contract extension with two club options that locks in the prime years of the young outfielder, something with which the Pirates have found significant success in recent years, a source with knowledge of the club’s dealings told Yahoo Sports.

The deal is believed to guarantee Polanco in the mid-$30 million range, the source said,