The Cardinals will promote top prospect Luke Weaver to take Michael Wacha’s spot in the rotation on Saturday, as MLB.com’s Jenifer Langosch writes. Weaver will become the second highly touted Cardinals right-hander to make his big league debut this week, as St. Louis called up Alex Reyes and inserted him into the Major League bullpen. The Cardinals will need to make a 40-man roster move to accommodate Weaver prior to Saturday’s debut.
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Weaver, 23 later this month, was the Cardinals’ first-round pick in 2014 (27th overall) and has quickly risen through the team’s system, reaching Triple-A last week after missing a large portion of the season due to a fractured wrist in his non-throwing hand. Despite his missed time, Baseball America rated him as the game’s No. 75 prospect on its midseason Top 100, and MLB.com rated him 93rd on its same list of top prospects. The Florida State product’s results in 2016 are borderline absurd, as he’s pitched to a 1.30 ERA with a 92-to-12 K/BB ratio and a 40.4 percent ground-ball rate in 83 innings. Jim Callis and Jonathan Mayo at MLB.com praise Weaver’s fastball, which sits at 94 mph and can touch 96 mph, as well as a plus changeup with good movement. His slider and curve are both inconsistent, they note, but either could develop into an average offering.
It’s unclear at this time if Weaver will continue to start beyond Saturday or if his promotion will amount to a one-time cameo prior to the expansion of rosters in September. General manager John Mozeliak spoke highly of Weaver’s control and his confidence in the rookie heading into this weekend’s outing, but he didn’t commit to anything beyond that date. “I feel like when you look at the ability to throw strikes, get deeper into games, I think that’s important,” said Mozeliak (via Langosch). “Candidly, [Weaver] only had one start in Triple-A, but I think he’ll still give us a good opportunity to win that game.”
Weaver will step into the St. Louis rotation alongside Adam Wainwright, Carlos Martinez, Jaime Garcia and Mike Leake, and in an odd way, the wrist injury actually helps the Cardinals. Weaver tossed 124 2/3 innings in 2015 between Double-A and the Arizona Fall League and surely would’ve been at or beyond that point right now had he opened the season healthy. However, he’s now still 40 innings behind his 2015 total, thereby reducing potential reluctance to drive up his innings total. If Weaver proves effective early on, he could give the Cardinals a consistent option in the rotation down the stretch, or at least as long as Wacha remains sidelined with shoulder problems. The Cardinals will control Weaver through at least the 2022 season, and the earliest he can be eligible for arbitration would be upon completion of the 2019 campaign.