The Major League Baseball offseason has officially begun. 

Just one day after the Milwaukee Brewers won the franchise's first World Series title, the offseason's first trade has gone through. 

The Boston Red Sox and Athletics swapped a Major League outfielder for a right-handed minor league pitcher on Thursday. 

According to USA Today's Bob Nightengale, the Red Sox have acquired 18-year-old Jareth Rayo in exchange for Nate Eaton. 

Eaton spent parts of two seasons in Boston, hitting .244/.329/.336 with two home runs, 10 RBIs, and an 88 OPS+ in 65 games. 

The 30-year-old was often sent back and forth between the Majors and Triple-A Worcester. 

"His speed and defense could give him a decent floor. Statcast pegged his sprint speed in the 96th percentile of qualified players this year," Darragh McDonald of MLB Trade Rumors wrote. "In his big league career, Eaton has 25 steals in 28 attempts. In 578 outfield innings, he has been credited with 14 Defensive Runs Saved, three Outs Above Average, and a mark of six from Fielding Run Value." 

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As for Rayo, he signed with the A's as an international free agent from Nicaragua last year. 

The youngster had a 5.50 ERA in 36 innings during the Dominican Summer League season. 

Rayo's long-term outlook is hard to project, but the Red Sox likely made this trade to clear up a roster spot for players on the 60-day IL. 

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