The MLB prospect world is a buzz right now. Several of the MLB top prospects in 2023 are coming up to MLB lineups recently and have been the talk of the baseball world. Struggling teams like the New York Mets and St. Louis Cardinals are making moves early to help bolster their rosters and turn things around with Mark Vientos and Mathew Liberatore respectively. Others like the Colorado Rockies are digging deeper into their system and prospect rankings to help their offense. It’s a pivotal time of the 2023 MLB season where MLB standings are shifting nearly everyday and teams know that promoting their top prospects can make the difference and fantasy baseball managers are looking for that edge for their fantasy baseball lineups and waiver wires as well. Don't forget to check out the 2023 fantasy baseball prospect rankings to see where this week's players rank! 


MLB Debuts for Top Prospects This Week

Mark Vientos — 1B/3B New York Mets

The Mets are finally doing it. They’re calling up another one of their big prospects in Mark Vientos who was simply hammering baseballs at Triple-A Syracuse this year. When we take a look at his 101 games played there last year plus the 38 in 2023 he’s combined for a .294/.374/.565 slash line with a .939 OPS, 37 homers, 109 RBI, and 92 runs in 139 games. He’s done all of that with a solid 25 or so percent K-rate and double-digit walk rate while playing first and third. The only real question for him is how he fits into the lineup right now but that’s likely at DH to get the struggling Daniel Vogelbach out of the starting lineup. This does however limit his fantasy baseball upside to likely qualifying only as a UTIL option.

Matthew Liberatore — LHP St. Louis Cardinals

We’ve seen glimpses of Matthew Liberatore in the majors with the Cardinals and they haven’t exactly been pretty. In his nine appearances, seven starts, last year he posted a 5.97 ERA (5.02 FIP, 4.93 xFIP, and 5.00 SIERA) over 34.2 innings. He gave up a bunch of walks and homers which didn’t help things either. This year at Triple-A Memphis however he’s been better. Over 46 innings in eight starts he’s pitched to a 3.13 ERA and 3.69 FIP while striking out nearly 11 batters per nine. Unfortunately the indication is that this is likely just a spot start to give the Cardinals’ other starters an extra day of rest but it could parlay into other chances in the next few weeks if there’s an opening.

Matt McLain — SS Cincinnati Reds

Another faster mover in the 2021 MLB Draft class, Matt McLain was called up earlier this week by Cincinnati as they need a boost for their offense. A highly-polished college hitter, he has made quick work of the minors with a healthy showing at Double- and Triple-A including a great feel for the strike zone, pop, and speed. Prior to coming up to the Reds he was hitting .348/.474/.710 with 12 homers, 40 RBI, 30 R, and 10 steals while walking nearly as often as striking out. He fits as a two-hole hitter in a MLB lineup and that’s where the Reds have been hitting him so far. A comp I have for him is Jose Altuve based on size and skillset and the fact that second base is likely his long-term spot.

Brandon Williamson — LHP Cincinnati Reds

It was a bit surprising to see Brandon Williamson get the call earlier this week. Sure, the first start went solidly over 5.2 innings with six Ks and one ER. However, the question remains how long he’ll remain in the majors given that he didn’t exactly look great over 21 starts at Triple-A between 2022 and 2023. In that span he pitched 89.1 innings with a 5.04 ERA, 5.51 FIP, 6.26 xFIP with a 1.73 WHIP and sub-par K- and BB-rates. So pick him up with caution if you need pitching help.

Brenton Doyle — OF Colorado Rockies

Has there been a hotter hitter over the last three games? Doyle has been on fire both in the batter’s box and defensively in center field in Coors. Over the last three games he’s hit three of his four homers on the year and has been hitting the ball more consistently. The batting average could use some help but there’s reason to believe it should continue to climb given the lowest he hit in the minors was .246 at Double-A Hartford which is a notoriously tough hitter’s park. If you need outfield help and he’s available he’s worth a shot given he’s got above-average power and a decent enough hit tool playing at Coors to give you some help.


MLB Prospects To Watch For Fantasy Baseball

Taj Bradley — RHP Tampa Bay Rays

When is he coming back up? That seems to be the biggest question with him at this point. There is some indication, based on recent pitch mixes in his last starts at Triple-A Durham, that they’re trying to refining one of his pitches a bit more while down on the farm. He’s stopped throwing his cutter as much and instead is working on the fastball more. That being said, the continued openings in the Rays’ rotation should provide plenty of chances for Bradley to return to the majors and continue his successful first run in Tampa.

Royce Lewis — SS Minnesota Twins

We talked about Royce Lewis last week as well. I’m not trying to continue harping on him but his rehab assignment has gotten off to a white hot start and he’s likely to be up with the major league team sooner rather than later. The taste of the majors he got last year was a nice showing; hitting .300 in 12 games in late 2022. While his main position is shortstop, he’s played third base, outfield, and designated hitter recently in the minors and that multi-position ability fits what the Twins’ could use with an opening at a few spots each week. If it’s not Lewis coming up, we should see Edouard Julien coming up again as Byron Buxton and Michael A. Taylor seem capable of splitting center field duties in platoon roles which opens the DH spot for Julien.

AJ Smith-Shawver — RHP Atlanta Braves

Stop if you’ve heard this before but… the Braves have another big time pitching prospect in their system. AJ Smith-Shawver was high school teammates with Bobby Witt Jr. and was taken seventh round of the 2021 draft as a two-sport star foregoing college. Since then, the now-20-year-old, has been on a rocket of a rise through the system reaching Triple-A in just his second full-season in the pros. So far in 2023, Smith-Shawver has thrown 21 innings at two levels over five starts with a 0.00 ERA and a 32:7 K:BB ratio. The FIP is a still a 2.24 mark which is impressive along with a .149 BAA. He’s just reached Triple-A and likely won’t be called up until the second-half of the season, unless he’s just too good to stay there. If you want a deeper league prospect in a keeper league, it’s hard to look past what Smith-Shawver has been doing and profiles as a number-three starter.

Ronny Mauricio — SS New York Mets

Why stop with Brett Baty, Francisco Alvarez, and Mark Vientos? Why not also call up Ronny Mauricio who’s been crushing balls at Triple-A Syracuse as well with a .354/.390/.615 slash line, seven homers, 30 R, 27 RBI, and eight steals. Sure Francisco Lindor is at shortstop and Jeff McNeil is at second base and there’s not much reason to take them out of the lineup. However, they have been working him at second base and can move McNeil to more of a full-time left field role.

Robert Gasser — LHP Milwaukee Brewers

Another injury to the Brewers’ starting rotation as Wade Miley has landed on the IL might open a spot. It’s often hard to judge how the Brewers will approach openings on their roster but, Robert Gasser is their top pitching prospect and is in Triple-A. While it’s not been the best run there with a 5.17 ERA in 31.1 innings so far (4.81 FIP, 5.48 xFIP), there’s some underlying better stats. His 11.2 K/9 is impressive as is his .216 BAA. However, the walk rate of 6.03 BB/9 and 1.47 WHIP aren’t as shiny. Gasser did post a 3.58 FIP in 26.1 at Triple-A last year and a 10.59 K/9. He will need to be added to the 40-man roster to get the call-up but his shot could be coming given the turnover in the Brewers’ rotation this year.


Fantasy Alarm is the home of expert MLB Fantasy content. We also bring you all of the best online sportsbook free bets & promo codes and fantasy sports bonuses. 

Related MLB Links: