The former Vanderbilt star didn't hit for as much power as some expected during his junior season, dropping his stock slightly, and the Astros snapped him up quickly.
"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," Elias said. "We saw his power in the Cape [Cod League] and in BP. Maybe it was just bad luck."
Gregor still hit .308 with 48 RBIs and a .440 on-base mark this season. He's also been praised for his eye, and he drew 54 walks this spring, good enough for sixth in the country.
Catcher Jacob Nottingham, a sixth-round California high-school product, will join the club's Gulf Coast League rookie team.
Nottingham hit .543 as a senior for Redlands High School, earning Citrus Belt League MVP honors in the process. Catcher is also one of the organization's weakest Minor League positions, but Nottingham isn't quite Major League ready behind the dish just yet.
"He's not a polished catcher, but there's a big arm and we hope player development can take care of the rest with those tools," Elias said.
Joining Gregor at short-season A ball in Tri-City are a pair of outfielders in 21st-round pick Jon Kemmer and 38th-round selection Ronnie Mitchell.
Houston has signed 17 of its 40 Draft choices, not including No. 1 overall pick Mark Appel and second-round choice Andrew Thurman, both of whom have reportedly agreed to deals.
Chris Abshire is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.