"I don't know right now," said Chris Gwynn, the club's director of player development, when asked where Peterson will play. "[We're] probably trying to find that out, but usually in any player, we try to give them a few positions that they can play."
Peterson prefers third base. It's the position he plays for the Mavericks, as well as the position he played at the University of New Mexico, where he starred from 2011-13. But Peterson will play anywhere if it means he reaches the next level faster.
"Whatever it takes to get me to the big leagues is what I'm going to do," Peterson said. "If [general manager] Jack Zduriencik called me and said, 'You need to catch,' I would be catching."
When Seattle selected Peterson with the 12th overall pick in the 2013 First-Year Player Draft, he became the highest selection in Lobos history, and earned a $2.759 million signing bonus. At 6-foot-1, 190 pounds, his profile is what Mariners management and fans yearn for -- a disciplined right-handed hitter who provides pop in the middle of a lineup.
In his second professional season, Peterson, 22, is batting .315 with 15 home runs and 64 RBIs in 60 games with the Mavericks.
Gwynn hopes making Peterson more versatile will increase his chances of quickly rising through the ranks. He's played nine games at first base this season after playing one game at first in 2013 while splitting time between Class A Short-Season in Everett and Class A Clinton.
"If Jack Zduriencik calls and says, 'Hey, has this guy ever played first?' I want to be able to say, 'Yes, he has,'" Gwynn said.
"I'm pretty acquainted with first base," Peterson said. "Let's just say that."
A few months ago, the Gilbert, Ariz., native spent his first Spring Training in the organization's Minor League camp, though he appeared in eight Cactus League games with Seattle. Petersen went 4-for-14 with a home run and four RBIs. The most memorable part of the experience was getting defensive tips from Mariners third basemen Kyle Seager.
"He said the key for him is just being consistent and making sure he can get to the balls he needs to, and just making the routine plays," Peterson said.
If Peterson makes a position change, it won't be the first time. He was a shortstop in high school.
"People seem to knock my defense," Peterson said. "That seems to be the knock they have on me. I feel like I do just fine [at third]."
Meanwhile, Peterson said his confidence at the plate increased after doing well in Spring Training, though he got off to what he characterized as a slow start in High Desert -- posting a .269 batting average in April before heating up.
"I think at the beginning of the year, everyone told me in High Desert you're going to hit 30 home runs there," Peterson said. "The ball carries. I thought about that a little bit too much and tried to do too much."
The Mavericks are at their All-Star break. Peterson's numbers (.941 on-base plus slugging percentage) aren't the sort that pin first-round Draft picks in the lowest rungs of the Minor Leagues, though there is the added complication of him playing home games in Adelanto, Calif., where the elevation is 2,871 feet and offensive numbers are inflated.
When reached by phone earlier this month, Mariners director of amateur scouting Tom McNamara didn't say when Peterson, the organization's top hitting prospect, could earn a callup.
"As long as he's playing and staying consistent, that will take care of itself, but we're proud of him and he's been hot lately, and hopefully he keeps it going," McNamara said.
If he continues at this rate, Peterson could soon be headed to Double-A Jackson. It's not the timetable he envisioned, but his first season was cut short last August when he was hit in the face with a fastball while playing for Clinton. The pitch broke Peterson's jaw, requiring surgery and a two-week hospital stay.
Three months passed before Peterson was cleared for baseball activities.
"My initial goal before I got cracked in the face was to make the big leagues by this September," Peterson said. "I don't know if that's going to be quite possible, but my next goal is to get a big league invite next year and hopefully get a chance to crack the big leagues to start the season."
Peterson wears a specialized helmet with an attachment that wraps around half his jawline -- the same used by Braves outfielder Jason Heyward. Last August, Heyward sustained a pair of jaw fractures when a pitch from Mets southpaw Jonathon Niese struck him in the cheek.
Peterson's jaw broke in eight places.
"It's pretty tough to come back from something like that," McNamara said. "I'm just glad he's out there playing."
In the process, Peterson's confirmed what the late Tony Gwynn saw when he managed San Diego State's baseball team after his Hall of Fame playing career. Earlier this week, Gwynn died at the age of 54 after a long bout with salivary gland cancer.
Late in Gwynn's managing tenure, Peterson was his opponent. SDSU and New Mexico are members of the Mountain West Conference and play often, which gave Chris Gwynn the best imaginable resource for a scouting report: His brother.
"He saw him a lot and he said that he was a really good hitter," Chris Gwynn said. "Tom McNamara and all the scouts said that he's a really good hitter. So it looks like to me he's a really good hitter."