"I would say we have a verbal agreement in place," Aiken said. "Next thing is to hammer out the details of the contract and hopefully that'll be done in the next week or two.
"We should know more when we're heading out to sign, take physicals, do all of that. Should be hearing back from the Astros in the next couple of days.
"I think they're just finalizing Ts and Cs."
Aiken, a high school left-hander from San Diego, was the top selection in the 2014 draft on Thursday night. MLB's slot value for that pick is $7,922,100, according to Baseball America. Aiken was not expected to be a difficult sign.
The various scouting publications -- like Baseball America -- all ranked Aiken as the top talent in this year's draft class. He is said to have a mid-90s fastball with a hammer curveball and a promising changeup.
The signing deadline for 2014 draft picks is Friday, July 18.