That groundwork led the organization to use its second-round pick (No. 68 overall) in Thursday's First-Year Player Draft on Williams, a player not necessarily projected by other clubs to be snatched up so early but one that the Cardinals believe could become a steal.
"That's one of the reasons why he wasn't one of these highly publicized players because he kind of came on the scene late," Kantrovitz said. "He wasn't this highly touted guy for us until I got that text from Fernando and Charlie. We really blanketed his starts from that point on and felt comfortable taking him on Day 1. I would be surprised if any other teams really had that type of comprehensive coverage on him."
Williams was the third right-handed pitcher the Cardinals picked on Thursday (and the second out of high school); the Cardinals followed that selection by taking another right-hander, Andrew Morales, three picks later.
Williams, like Cardinals first-rounder Jack Flaherty, was a two-way player in high school. As a junior, Williams went 4-1 with a 2.58 ERA and hit .394. Williams then helped pitch his school to a state championship this season and finished 2014 with an 8-2 record and 0.97 ERA in 65 innings (11 games). He struck out 72 and walked 22.
"Ronnie is an electric athlete, and he has a delivery that we fell in love with," Kantrovitz said. "You can tell by his delivery how fluid it is, how connected it is, how repeatable it is. You can't have that type of delivery without being a great athlete. This guy is just outstanding."
The Cardinals also clocked Williams' fastball consistently at 96-97 mph.
The Hialeah, Fla., native has committed to play at Florida A&M University. The Cardinals expect that they'll need to offer Williams appropriate slot money ($833,900) in order to get him to back out of that college commitment.
The Draft will continue on Friday with Rounds 3-10. The MLB.com pregame show begins at 11:30 a.m. CT, with exclusive coverage of Rounds 3-10 beginning at noon. The final 30 rounds will then take place on Saturday.
Jenifer Langosch is a reporter for MLB.com. Read her blog, By Gosh, It's Langosch, and follow her on Twitter @LangoschMLB. This story was not subject to the approval of Major League Baseball or its clubs.