Outfielder Alex Presley, who spent two seasons in the Astros' organization, is fighting for the final outfield spot on the 25-man roster. Brett Phillips came over with Santana as part of last July's mega-deal that sent Carlos Gomez and Mike Fiers to Houston.
Unsurprisingly, the teams were unusually friendly, even by Spring Training standards.
"There have been a lot of pregame hugs in center field," Brewers manager Craig Counsell said.
Milwaukee general manager David Stearns was the assistant GM in Houston under Jeff Luhnow for three seasons. Given Houston's abundance of young talent, Counsell said he expected Stearns to draw on talent from his former organization.
"Any time your GM comes from the organization, you're going to have players from there because he's familiar," Counsell said. "He trusts them and you feel like you know what you're getting. There are guys here who are a major part of this team.
"We have a full squad of them, no doubt."
The heavy Houston influx has helped the team coalesce quickly.
"A lot of us were all teammates at one time or another and reunited here," Presley said. "You're happy and comfortable with them. It makes Spring Training and building camaraderie easier."
Added Carter: "It wasn't walking into a place where you didn't know anybody."
For Santana, who mashed in Triple-A for Houston but never translated that to Major League success with the Astros, it's a precursor. With a Luhnow understudy at the helm, a slew of his former team's players and the Brewers in the building process, Milwaukee might be aiming for the National League version of the Astros' recent resurgence, if perhaps focused more on 2017 and beyond.
"We have a young club, young talent and the puzzle is ready to be put together," Santana said. "It definitely reminds me of coming up through that organization."
Chris Abshire is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.