One reason the Pirates traded Adam Frazier to the Padres was their knowledge of San Diego’s minor league system due to the Joe Musgrove deal. Ben Cherington shows his knowledge of Tucupita Marcano abilities, for example:

“He’s a skilled player, always been really young for his levels,” Cherington said. “He’s young this year for Triple-A, and he’s performed really well despite being a young player everywhere he’s been. He’s got a good feel to hit, a good decision-maker in the box, controls the strike zone, has always had a good ability to make contact, line-drive approach. He’s grown into a little bit more power this year.

“He’s a versatile defender. We see him with the ability to play shortstop, second, probably move around the entire infield and outfield, if needed. So that versatility is appealing. And then all the work we’ve done on him suggests that the character and work ethic and the aptitude is strong, also, so we feel good about that along with the other two guys that we’re getting.”

Post-Gazette.com

On top of that, the article implies that this was the best deal the Pirates could make. There were similar offers, but the experience scouting SD players won out.