Mariners Draft Profile: Rockwall-Heath (TX) SS Jett Williams
As far as prep players go, Jett Williams has as much upside as any of them. While he does not have the family name recognition/reputation as other top prep prospects (Druw Jones, Justin Crawford, Jackson Holliday and Elijah Greene to name a few), he has comparable talent and, in some ways, even better tools.
Williams is a great defensive shortstop. He has elite raw arm strength for his age and is extremely agile. For context: Williams' 60-yard dash time of 6.47 seconds ranked in the 98th percentile amongst all draft-eligible prep players. He also had a 1.55 10-yard split, which ranked in the 91st percentile.
Stealing 15 bases last season, Williams' speed shows up on the field. His hardest throw to first base from shortstop was registered at 92 MPH; MLB star shortstops Fernando Tatís Jr. and Javier Báez have maxed out at 94 MPH, meaning the 18-year old, 5-foot-8, 187-pound Williams could realistically develop to at least match them by the time he reaches the major leagues.
For additional reference: the "consensus" top shortstop in this year's class, Holliday, put up far inferior numbers, with lagging arm strength, speed, and agility. Williams will be a better defender than Holliday, who might not even stick at shortstop.
Some of the other metrics Williams recorded at Perfect Game showcases are stunning. This April, he registered a max barrel speed at 89 MPH, which is higher than Jones and Greene—two prep players who are known for their raw power. Williams' bat speed might be the best amongst all high school players in this year's draft. And while he does not currently possess much game power, it is possible he'll be able to tap into it after some development in a major league system.
It's uncertain if Williams' frame will be conducive to power long-term, but his quick hands suggest he will at least be able to keep up with velocity and make a lot of contact. Williams hit five, nine triples and five doubles last season against Texas 6A competition while slashing .347/.514/.723. He is a guy who can fly around the bases and get extra-base hits, but just not as many home runs.
Williams does have a flat bat path on his swing, though he maximizes its potential with his barrel speed, allowing him to get out in front of pitches and tap into his pull-side power. If he is able to get more hip-torso separation during his swing (which is honestly a pretty big "if"), he could potentially unlock serious game power despite his size. Williams was also elite at controlling the zone this season, with very few chases or whiffs.
While Williams is a great prep player, he likely would not command too much more than slot value upon being drafted by the Mariners at pick No. 21. According to Prospect Live's Joe Doyle and Prospect Insider's Jason Churchill, the Mariners have him Williams as their "1B" option to their "1A" in Campbell shortstop Zach Neto.
If the interest is legitimate, Williams presents value, raw tools to dream on and future up-the-middle impact that makes him appealing at for Seattle.
