But inexperience hasn't hindered the trio thus far, and there's a legitimate chance all three will make the big league roster out of camp.
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"We took them for a reason," said Padres general manager A.J. Preller. "I don't think we took all three guys saying we have to only keep one. ... We're going to go with the guys that earn it, and there's definitely a scenario where all three guys end up making the club."
There's plenty of incentive for the Padres to find room on the roster for the three high-ceiling youngsters. Per Rule 5 Draft stipulations, they must remain with the big league club for the duration of the season or be offered back to their original team.
In that regard, Diaz, the team's 22nd-ranked prospect, would appear to be the likeliest keeper. The Padres plan to stash the right-hander in their bullpen, much like they did with Luis Perdomo early last year.
Perdomo earned himself a place in the starting rotation by mid-June, and while they don't expect quite so quick a progression from Diaz, the Padres view Diaz as a starter long-term.
It might be trickier to find space on the roster for Torrens, a catcher, and Cordoba, an infielder. But the duo will be given chances to showcase their talents.
"Torrens is going to catch innings, and he's going to be out there with an opportunity to compete," manager Andy Green said. "Cordoba will as well. They'll be playing early and consistently and receiving opportunities to prove who they are."
Torrens, the Padres' 23rd-ranked prospect, might have the toughest road ahead, given the nature of his position. The Padres, who traded infield prospect Josh VanMeter to the Reds for Torrens' rights, have done their best to prep him for the challenge.
Catching coordinator Ryley Westman and bullpen instructor Justin Hatcher went to Venezuela this offseason to work with the 21-year-old backstop. They covered receiving, blocking and even knowledge of the individual pitchers on the Padres' staff.
"All the stuff he's done connecting with pitchers, he's been really impressive," Green said of Torrens. "It's a lot of work. It's a steep, steep learning curve. He has not shied away from it."
It's been a whirlwind for Torrens, who was mid-workout when he learned -- via Twitter -- that he was heading to San Diego.
"I was definitely surprised," Torrens said. "At first, I was really kind of in shock because it's not something I was expecting. But once I found out, I got really excited, just because of the opportunity."
Cordoba and Diaz have impressed as well. During Tuesday's workout, Cordoba, the 21st-ranked prospect, hit a rocket off the left-center-field wall during live batting practice on the main field. A few minutes later, Diaz took the mound and whiffed Cordoba on five pitches.
The three players already feel as though they belong.
"Everyone here is really good in terms of relationships and camaraderie," Torrens said. "You can learn from the young guys and the guys with experience, too. It's a good atmosphere."