SCOTTSDALE, Ariz. -- Anytime someone insists that left-handers are born, not made, invoke the saga of Ty Blach.
The Giants lefty is a natural righty. He does everything right-handed -- eating, playing golf, swinging a bat and throwing a football. Everything, that is, except pitch.
Blach, a leading candidate to occupy one of the two vacancies at the back end of the Giants' starting rotation, fits the profile of many southpaws. He doesn't throw particularly hard, but he doesn't have to. Deception, novelty and ample movement on his pitches help sustain him.
Blach, 27, owes it all to a family friend, Mike O'Day, who didn't fully realize what he was doing when he exercised his influence on Blach.
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Residents of suburban Denver, O'Day often played catch with Ty the toddler at cookouts and on camping trips. The well-meaning friend didn't convert Blach immediately.
"There's pictures of me throwing right-handed when I was 3 or 4, but I don't really remember that. I always remember being a lefty," Blach said on Thursday.
Then came the afternoon when O'Day introduced Blach to the society of southpaws.
"He had his ball and I was tossing it to him," O'Day recalled. "Every time he'd pick it up with his right hand, I'd put it back on the ground and tell him to pick it up with his left hand and throw it to me.
"Everyone asked, 'Why are you doing that?' I said, 'Because left-handers are a better commodity in baseball. So I'm going to make him left-handed.' Everyone thought I was absolutely crazy. But it actually turned out to be OK, I think."

O'Day was not pushing Blach to be a big leaguer.
"At the time, it was a funny thing," O'Day said. "Friends said, 'Oh, really, like that's going to make a difference.'"
It ultimately did. Blach excelled at Regis Jesuit High School in Aurora, Colo., and at Creighton University en route to being selected by the Giants in the fifth round of the 2012 Draft.
Being a lefty, Blach said, "creates so much value, especially when you get to this stage in your career. Whether it's starting or relieving, you seem to get more opportunities being left-handed. There's not quite as many of us around. ... It creates different movement and it creates spin that guys aren't used to seeing all the time."

Blach seized his advantages last year as a rookie to post an 8-12 record -- respectable, given the Giants' overall performance -- with a 4.78 ERA.
"There were a lot of really good things to build on [from] last year," Blach said. "Yeah, I had some bumps here and there, but it was really great to be able to be up here, get that experience and understand what it takes to have success at this level. It was great for me to take that to the offseason and know what I needed to work on."
All it took for Blach to embark upon this path was one little game of catch that turned a righty into a lefty.
"It became a natural thing to him," O'Day said.