Mariners love upside of slimmed-down Aro

PEORIA, Ariz. -- Jonathan Aro is not sure when it's going to happen, but he's certain he's going to pitch in the big leagues this season.
The Mariners hope so, too. The club traded proven pitchers Carson Smith and Roenis Elias to Boston for the right-hander and starter Wade Miley in December.
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"I think he's got a lot of upside. I think he's got a big-time big league career ahead of him," Mariners manager Scott Servais said. "When does it all start for him? I'm not quite sure. I saw him in the Dominican before we acquired him and I was excited when we got him."
Aro, 25, went 0-1 with a 6.97 ERA in 10 1/3 innings over six relief appearances for Boston last season and went 3-3 with a 3.04 ERA in 34 outings for Double-A Portland and Triple-A Pawtucket. He's ranked No. 29 on Seattle's Top 30 Prospects list.
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Told he needed to show up to camp in better shape, Aro ramped up his workouts back home in the Dominican Republic over the winter and changed his diet. The results -- he lost 11 pounds in the first few months of the offseason -- were noticeable, and he eventually lost five more pounds. He jokes that his mother, Ana Rosario, stepped up her cooking game when she noticed her son losing weight.
"Mom likes me chubby and she was like, 'Why am I making you all of this food if you are not going to eat all of it?'" Aro said with a laugh. "I think that she understands now that I have to work for my future. She's my biggest supporter and she wants the best for me. I know she's very proud of me."