Gregor said he had just left a team meeting when one of his teammates delivered the news.
"We just went crazy," Gregor said. "It was surreal, and I was speechless. I was shocked when I got picked in that spot. I had no idea where I was going to go. It's an honor to be selected by them. It's a dream come true to be drafted."
Gregor, a junior, hit .309 for the Commodores in the 2013 regular season and SEC Tournament. He had three home runs, 43 RBIs, 51 walks and a .443 on-base percentage. Some believe that Gregor may even be athletic enough to play a corner-outfield position professionally. Even if he is able to handle the outfield, Gregor will be carried by his bat.
The Carmel, Ind., native hit .329 with eight home runs and 21 RBIs for the Orleans Firebirds of the Cape Cod League last summer. He also walked 38 times.
"He was viewed as a top-two- or three-round pick after last summer, but the scouts didn't see the homers this spring, and it hurt his stock," said Astros director of amateur scouting Mike Elias. "We saw his power in the Cape and in BP. Maybe it was just bad luck."
Gregor seems likely to sign, given his high Draft slot, but he said he's not thinking about a decision until Vanderbilt's season is done.
"Right now, I'm undecided, but the next few weeks are about my teammates, getting to the College World Series," Gregor said. "I'll make the decision with my family, because it's a big one."
Chris Abshire is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.