RonCoomer

Considering that Deduno has 12 more career starts than Gibson (41 vs. 29, respectively), the Twins have given him more of a chance to succeed simply because he's been around the club longer. Anyway, even though Deduno has a lower ERA this year, Gibson has been looking better on several metrics: In 2014 Gibson is doing slightly better than Deduno in terms of FIP (3.84 vs. 4.09), WHIP (1.28 vs 1.41), and BB/9 (2.5 vs. 3.9). He's also doing negligibly better with K/BB--1.80 for Gibson vs. Deduno's 1.77, despite Deduno's higher K/9. If you look at their career lines some of these differences are even more stark in favor of Gibson. So I'd say that Gibson has done more and has most definitely earned his spot in the rotation over Deduno.