He is Evan Marshall, a 6-foot-2, 220-pound right-hander who was the D-backs' fourth-round selection in the 2011 First-Year Player Draft.
Marshall, 22, currently is ranked by MLB.com as No. 13 among the organization's Top 20 prospects. He is having a solid AFL season and was 0-1 with two saves and a 1.93 ERA in his first eight games with a WHIP of 0.96.
Marshall's second professional season was in 2012 with Double-A Mobile. He helped the team claim the Southern League championship with a 6-3 record, 3.51 ERA and 16 saves in 42 games.
Marshall was a starter in high school in Sunnyvale, Calif., near San Francisco, but became a reliever in college at Kansas State.
He was a fan of most of the Bay Area sports teams and attended some San Francisco Giants games at Candlestick Park, watching a third baseman named Matt Williams.
Because of those childhood ties, Marshall admitted a small part of him was happy the Giants recently won the World Series, "but I am a Diamondback now, and everything I am doing is for them."
And Williams, who is now Marshall's manager with the Rafters, said the right-hander can be used in a variety of situations.
"[Marshall] can be a setup guy, a closer. He is a guy who can throw multiple innings, and he gets some good sink on his pitches," Williams said.
Marshall is ready for anything as long as it gets him to the Major Leagues.
"I'll work in the seventh, eighth, ninth innings -- a combination. I will close if that's what they want," he said.
"I'm having a great time out here. It's been a lot of fun. This is an awesome facility [Salt River Fields at Talking Stick, spring home of the D-backs and Colorado Rockies]. My arm is feeling as good as it has all year, and a lot of that has to do with the recovery prescribed by the D-backs after the long season.
"I am learning with every experience. These guys are good hitters out here."
Starters, Marshall said, have a better throwing cycle, can get into a routine. A reliever has little or no routine, but he doesn't mind.
"You have to make sure you are ready to produce at any time," said Marshall, who is working on all his pitches this fall. "[I'm] just trying to stick to the game plan. I've been throwing with some sink, and I am working on finishing my fastball."
Marshall said his arm slot is naturally compatible with throwing the sinker. And although he hasn't had big power numbers, Marshall said those aren't always necessary to be successful.
"[Baltimore Orioles closer] Jim Johnson had more saves this year  than strikeouts , so it's also about using the right combination of pitches," Marshall said.
Marshall is not sure where he will be headed next spring. The right-hander is hopeful it will be a similar experience to last spring, when he was with the big club as a non-roster invitee.
"Baseball is a lot of fun to begin with, but when you get to that upper level, it's even more so," Marshall said. "You get to work with some guys who have been around a long time. That really helps. You learn a lot."
If things work out and Marshall has a good spring, who knows? Maybe he can earn a permanent spot on the big club this spring.