In exchange for a fee of $200,000, the Diamondbacks released Barnette on January 5, 2010, so that he could sign with Nippon Professional Baseball's Yakult Swallows.

At the conclusion of the 2015 NPB season, his sixth with the Yakult Swallows, Barnette had appeared in 260 career games as a relief pitcher, compiling an 11–19 record and 97 saves with a 3.58 ERA and a 1.26 WHIP.

On September 24, he broke the Swallows single-season record for saves, 37, that had been jointly held by his pitching coach at the time, Shingo Takatsu (2001), as well as Ryota Igarashi (2004) and Hirotoshi Ishii (2005).

[citation needed] Barnette signed a two-year deal with the Texas Rangers of Major League Baseball on December 15, 2015.

[11] Written by Aaron Fischman and authorized by Barnette himself, legendary agent Don Nomura penned the foreword, the book currently sits in the library of the National Baseball Hall of Fame and Museum and it was named a finalist for the prestigious Casey Award that honors the best baseball book each year.

The Blue Jays went on to sweep the Rangers in the opening round, eliminating them for a second straight year, though Barnette's rookie season went down as an unmitigated success.

By going to Japan without any prior major league experience and ultimately earning a major league deal before stringing together multiple strong MLB seasons, he'd usher in a new era of pitchers following a similar formula, with the San Diego Padres' All-Star closer, Robert Suarez, as the most prominent example.