Springer briefly visited Minute Maid Park before hopping a plane back to his home in Connecticut.
"It's an incredible ballpark," Springer told MLB.com. "The atmosphere and the whole feel of the stadium was something special to me. [Houston] is an incredible place. I didn't know it was as big as it was."
Springer, 22, was drafted with the No. 11 overall pick out of the University of Connecticut, where he hit .343 with 12 homers, 77 RBIs, 31 stolen bases and a .450 on-base percentage during his junior season. He briefly met Astros manager Brad Mills on Friday.
"He seemed like a great guy," Springer said. "He's a baseball guy and was fun to be around for a while. I was only there a short time. It was basically in and out."
Astros general manager Ed Wade wanted to get the physical done in case Springer signs near the deadline.
"If this thing drifts to the Aug. 15 deadline, we don't have to set our hair on fire at that point to try to get an agreement in place," Wade said. "He passed it with flying colors. It was an in-and-out deal. [Team medical director] Dr. [David] Lintner and the people at Methodist Hospital paved the way for him. The hard part is done. Now the easy part comes, getting him signed."
Wade said he expects negotiations to continue until the deadline. The Astros are hoping to sign Springer, third-round pick Jack Armstrong -- who's currently pitching in the Cape Cod League -- and 13th-round pick Horace Stubblefield, a right-handed pitcher from Lufkin, Texas.
Wade reiterated Springer's trip to Houston wasn't a recruiting visit.
"I don't think it's fair to bring a kid in under those circumstances and it shifts into a sales pitch," he said. "I did tell him what a really good organization we've got and how we would really like to have a lot more younger players coming through the system and how we're the land of opportunity."
Last week, Springer and his father met with the general manager of the Long Island Ducks of the independent Atlantic League. His father said the meeting was done for his son to explore his options for beginning his professional career in case he doesn't sign with Houston.
Brian McTaggart is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.