McGuiness spent a majority of the 2013 season with Triple-A Round Rock, where he hit .246 (89-for-362) with 29 doubles, one triple, 11 home runs and 63 RBI in 104 games. He also recorded a .998 fielding percentage in 90 games at first base with the Express after being charged with just two errors in 853 total chances.
25-year-old McGuiness also made his big league debut last season with the Rangers and went 6-for-34 (.176) with one double and one RBI in 10 games.
In 2012 with Double-A Frisco, he hit a career-high 23 home runs, which was tied for the fourth-most among all Texas League hitters, recorded a career-best 77 RBI, which ranked seventh in the league, walked 69 times, which was fourth in the league, and had an .840 OPS, which was eighth-best among Texas League hitters.
McGuiness was originally selected by Boston in the 13th round of the 2009 First-Year Player Draft before being acquired by the Rangers on July 31, 2010. He was then selected by Cleveland in the Rule Five Draft on December 6, 2012, before being returned to the Rangers organization on March 27, 2013.
The left-handed hitting McGuiness has recorded a career batting average of .257 (421-for-1637) with 105 doubles, two triples, 62 home runs and 275 RBI in 454 games in the minor leagues.