"I was trying to nitpick a little, so I think that's why I walked that guy," he said. "I was a little nervous, but other than that I was fine. I just have to keep doing what I do."
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Greene is in his first big league camp and smilingly acknowledged he'd be happy returning to the Double-A New Hampshire Fisher Cats where he went 3-1 with a 4.68 ERA to end his 2015 season.
"I wasn't there for too many days. So I'd be excited to go back and prove, 'I've got this.' Get the grind going and get the fastball command right and keep everything moving," he said.
In the end, circumstances and his performance will dictate whether or not the pitcher ranked as the Blue Jays' second-best overall prospect by MLBPipeline.com makes his Major League debut in 2016 or not.
"It's tough to say," noted manager John Gibbons. "Actually, a lot of [what was done last season] was out of necessity. We were trying to fill some holes in our bullpen. They were young, but they were our best candidates and the best arms. And they had really good springs. It was a gamble, but it really paid off with Osuna. Castro struggled a little bit, but eventually he'll be fine.
"With an arm like that, [Greene's] shown he can pitch. He'll control that. If he's really good, I'm sure they'll bump him. If not, we'll wait until he's good and ready. But I've been very impressed. I heard a lot of things about him. I had never seen him pitch before he got here. He's got a great arm. That's pretty obvious. And he looks like he knows what he's doing, too. He's not just heaving it, you know?"
Greene said he's just thrilled to be around the big leaguers. He said that when he was 14 years old he caught a home run ball hit by then-Dodgers catcher Russell Martin into the left-field pavilion at Dodger Stadium. Now they're teammates.
"I'm star-struck still, man," he said. "I caught one of Russell Martin's home run balls when I was like 14 years old. Brad Penny. R.A. Dickey. Guys like that. I'm in awe every day. I go up to them, now that I get to wear the same uniform, and it's incredible. Words can't even describe it. Just learning from them. No learning experience I've had can compare to the two weeks that I've been here."
Observed Gibbons: "He's a fun-loving kid. A good kid to be around. He's just soaking up everything he can. He's the top pitching prospect in our organization, so when his time's right he's got a chance to be really, really good."