Billy Butler told MLB.com’s Dick Kaegel that he and the Royals have agreed to a four-year, $30 million contract extension.

The deal buys out all three of his arbitration-eligible years plus one year of free agency. Butler is represented by Greg Genske of Legacy Sports.

Butler filed for $4.3 million in arbitration earlier this week while the Royals countered with $3.4 million. Kansas City recently picked up an extra $12.4 million when Gil Meche unexpectedly retired.

Butler, 25 in April, has hit .309/.375/.480 with 36 homers over the last two seasons. Just 28 players boast an OPS that high during that time (min. 1,000 PA), but Evan Longoria, Carlos Gonzalez, Ryan Zimmerman, Troy Tulowitzki and Butler are the only ones to do so at age 25 or younger.

Clearly, the Royals first baseman has emerged as one of the game’s most dangerous young hitters.

Kansas City currently owns the game’s best farm system, and they’ve now ensured that their best position player at the Major League level will be around when some of those highly touted prospects start to arrive.

This is yet another good move made by Royals GM Dayton Moore. The signing of Jeff Francis last week has been considered by some to be the best deal of the winter thus far.

The addition of the Billy Butler extension shows that GMDM somewhat knows what he is doing.

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