"Every at-bat is challenging, and I just have to keep improving every day," said Polanco, who analyzed the difference between Major and Minor League pitching, a bridge he has a couple months to cross, with impressive insight.
"Our job," general manager Neal Huntington said, "is to put him in position to thrive, not just survive. We're excited by where we believe he can go and how quickly we can get him there to help us win Major League games as quick as possible."
Also optioned to Indianapolis was right-handed reliever Duke Welker.
Polanco's stay in the Major League camp was brief and impressive, satisfying expectations entering his first extensive exposure in a big league environment.
"We couldn't be happier with the development," Pirates manager Clint Hurdle said. "We want him to go down and face the challenge. Every time he steps into the box, there's going to be a pitcher thinking, 'That's a springboard to the big leagues,' whether it's an older or young pitcher. So what an opportunity for him to go and add quality at-bats.
"To get him in that environment ... he's hungry to go. We want him, when he gets back, for it to be for good."
Appearing in 10 of the Bucs' first 15 Grapefruit League games, Pittsburgh's No. 1 prospect went 6-for-22 (.273) with two doubles and one home run.
Not seen in that batting line is the education Polanco received.
"They pitch backwards," Polanco said of the big league pitchers he got to face, which included the likes of A.J. Burnett, Detroit's Rick Porcello and the Yankees' David Phelps -- off whom he hit his only homer. "On 3-1 and 2-1 counts, they throw offspeed, a curve or a change. They don't throw fastballs, like in the Minor Leagues.
"They have more command, and they throw out and in. So, here, you have to focus more, concentrate on every pitch."
"[Polanco] has to stay focused pitch to pitch in the outfield, too," Huntington said. "He showed us his tremendous skill -- and showed us his youth at times. He hit a couple of Major League pitchers' offspeed pitches in fastball counts and did some damage on them. But we also saw him swing through some pitches by trying to do too much, as he got long [took a swing too big].
"He has to keep the swing short, and recognize how to handle offspeed pitches in fastball counts, because he's going to get that from Day 1 in the big leagues. So he'll have the opportunity to see that from better competition [in Triple-A] before we ask him to do it at the Major League level."
Polanco got a lot of that in the Dominican Winter League, a test he passed convincingly by winning both the Most Valuable Player Award and the Rookie of the Year Award. It was part of a natural progression, but still, he admitted, not up to Major League caliber.
"It's a little bit better here," Polanco said of the pitching, "with more command."
Polanco admitted to receiving some advice from Starling Marte, the fellow Dominican outfielder who underwent a similar process a couple of years ago. Marte was optioned to Indianapolis in 2012, despite a very strong showing in Spring Training, and he was deemed ready to join the club in late July that season.
"He said he went through the same thing and told me, 'Keep playing. Keep doing what you're doing, and see what happens,'" Polanco said. "I know I'm young. I'll have to wait until they call me up."
Huntington acknowledged the Marte similarity -- and more.
"It's similar to what Marte went through, and what Andrew [McCutchen] went through," the GM said. "[Polanco] is a very talented young player, and his reputation is preceding him. He'll see a lot of 2-0 changeups and fastballs just off the plate as [pitchers] try to get him to expand the zone.
"But he's a very smart, very hard-working young man. We're enthusiastic about so many things he can do on a baseball field. This will just give him more experience to refine the skills that he has."
McCutchen had to be particularly patient, waiting through 881 Triple-A plate appearances and a total of 511 Minor League games before joining the Pirates for keeps in mid-2009. Marte had 431 Triple-A plate appearances and 464 Minor League games prior to his callup on July 26, 2012.
Polanco has played 410 Minor League games, but he will start this season with a grand total of nine plate appearances at the Triple-A level. If he gets his promotion prior to Sept. 14, he will arrive at 22 -- at the same age as McCutchen and a year younger than Marte.
Welker, 28, appeared in six Spring Training games, allowing seven hits and six earned runs in 5 1/3 innings.