One of the more unusual rookies making his MLB debut in 2016 is Texas Rangers relief pitcher Tony Barnette, entering the league as a very old newcomer at age 32. His background is as unusual as his birthday.
Barnette was originally drafted by the Arizona Diamondbacks in the 10th round in 2006 from Arizona State University. He advanced steadily as a starting pitcher, posting solid seasons in Low-A in 2007 (3.60 ERA, 108/28 K/BB) and Double-A in 2008 (3.87, 133/42). In Triple-A in 2009 he won 14 games with a 121/61 K/BB but the difficult pitching environment at Reno in the Pacific Coast League elevated his ERA to 5.79.
In 2010 he signed with the Yakult Swallows of the Japanese Central League. He struggled that year (5.99 ERA) but in 2011 he took a large step forward, seizing the closer role and nabbing 22 saves. Aside from an injury-plagued year in 2013, he remained a dominant bullpen force in Japan, saving 117 games through 2015.
Barnette decided to return to the United States for 2016, signing a two-year free agent contract with the Texas Rangers. He was excellent in spring training (1.86 ERA, 13/0 K/BB in 9.2 innings). He got hit hard in his big league debut on April 5th (0.2 innings, three hits, two runs) but followed up with a scoreless inning on April 6th. Given his strong spring training performance he should get a full chance to prove himself.
Barnette is a 6-1, 190 pound right-hander born November 9th, 1983. He works with a fastball in the low-90s and will mix in some mid-80s change-ups, but he relies heavily on his 84-88 MPH slider/cutter as his key pitch. There's a bit of hesitation in his delivery which adds a different look.
There doesn't seem to be any reason why Barnette can't be an effective middle reliever. Fantasy value would depend on the potential for save opportunities, but he should be able to contribute quality filler innings.
Here's some video from Japan