The Astros have agreed to terms with fourth-round pick Rio Ruiz on a $1.85 million bonus.

That's the biggest bonus compared to assigned pick value thus far in the 2012 draft, coming in at $1,489,800 over the $360,200 allocated for the 129th overall pick. Ruiz beats the standard set by fellow Astros draftee Lance McCullers Jr., who signed for $2.5 million as the 41st overall pick.

Ruiz had a chance to go in the first round before missing most of his senior season following surgery to remove a blood clot in his neck in March. The Bishop Amat HS (La Puente, Calif.) star projects as a third baseman with an average bat, plus raw power and a strong arm. He had committed to Southern California.

Ruiz's signing effectively ends any chance Houston has of landing 11th-rounder Hunter Virant, a California high school lefty who dropped because of a seven-figure price tag. The Astros still should be able to sign their three College World Series participants in the first 10 rounds (Florida shortstop Nolan Fontana and outfielder Preston Tucker, UCLA catcher Tyler Heineman) without blowing past their bonus pool of $11,177,700 by 5 percent. If they did exceed their pool by that much, it would cost them a first-round pick next year.

View our Astros Draft Database here.