The first half of the 2023 MLB Season is coming to a close with the All-Star Game getting closer. With the All-Star Game comes the 2023 MLB Draft and an updated MLB Prospect Rankings coming next week. Prior to those new rankings though, there are top prospects who have been promoted and have been playing like All-Stars over the last few weeks. The Baltimore Orioles made a splash with the promotion of Colton Cowser to the major league roster while the Detroit Tigers moved their top prospect up to Triple-A in Colt Keith. Now is a perfect time to see what other top prospects might be hitting or pitching their way to the majors in the second half of the 2023 and can help your fantasy baseball lineups through the rest of the year.


Colton Cowser — OF Baltimore Orioles

The number two prospect for the Baltimore Orioles is the latest youngster to join the major league roster. And boy is he another doozy of a bat. Cowser grades out as a 55-grade player across the five main tools. While none are necessarily a plus, above-average across the board is still a serious fantasy player in terms of upside. I’ve written up Cowser earlier this year because of his numbers at Triple-A Norfolk so I’m not doing a deep dive now. However, as a baseline of what he’s capable of when he’s at his best, Cowser is likely a .280 hitter with enough power and speed to be a 25-25 outfielder in the middle of an MLB lineup.

Colt Keith — 2B/3B Detroit Tigers

Another prospect I’ve mentioned before is Colt Keith and his offensive upside. The Tigers offense is horrid this year and has been for a while but there’s hope on the horizon. Keith has a lot of pop and average at his disposal and has put it on display enough that he was promoted from Double-A to Triple-A a week ago. Since getting to Triple-A, he’s been on fire hitting a few homers and over .400. Now, don’t expect a quick call-up to the majors but it’s a good sign he’s hit the ground running at Triple-A. This promotion does put him on pace to be a threat for the starting second or third base role early in 2024 in Detroit.

Tyler Soderstrom — 1B/C Oakland A's

The A’s haven’t been newsworthy, for many good reasons, this year but they have a few prospects who have been. Soderstrom has been on an absolute tear of late with eight homers in the last 20 games, 80 at-bats, while hitting .263/.322/.600 with 19 RBI and 14 R. He’s been splitting time between behind the dish and first base which certainly makes him intriguing, as does the bat. Catcher and first base are two of the shallowest positions for fantasy baseball and match that with at least above-average power and a solid Hit tool and you have a solid combo. The downside is the K-rate that’s hovered at more than a K/Gm for much of his career. If he keeps producing though, the K-rate isn’t that big of an issue.

Zack Gelof — SS Oakland A's

I said they had a few prospects of note; Zack Gelof is one of the others. The shortstop has been slashing .311/.386/.578 over his last 23 games and 90 at-bats. Add six homers, 19 R, 18 RBI, and five steals to that stat line and it’s pretty newsworthy. Gelof has been a threat to make the MLB roster since making Triple-A Las Vegas late last year and with his latest hot streak, he’s starting to press for real. The A’s haven’t gotten anything outside of a few regulars in the lineup and we could see them make moves to start bolstering the lineup in the second half with Soderstrom and Gelof cracking the starting nine.

Cade Marlowe — OF Seattle Mariners

It has been a terrible year for the Mariners’ offense with them struggling in most facets of the game including strikeouts where they are one of the worst teams in the league. Gee, I wonder if there’s anyone they can promote to help the offense get a boost? Cade Marlowe perhaps. Over his last 25 games and 99 at-bats, Marlowe is hitting .293/.388/.586 with seven homers, 22 RBI, 21 R, and 11 SB. He’s also walked 16 times in that span as well. That by itself is noteworthy for a potential Seattle hitter. While Jarred Kelenic started off well he’s not doing much at the plate of late and could leave a spot open in the outfield for Marlowe to get a shot and boost the offense. Long-term, Marlowe is a guy with above-average Power and plus Speed with an average Hit tool.

Trey Cabbage — OF Los Angeles Angels

Who? Exactly. He’s not a well-known prospect in the least. He’s not in my rankings nor is he in most analysts Top-30 Angels prospect rankings, yet he should be watched. Over his last 108 games between Double-A and Triple-A Salt Lake, 78 games at Triple-A, he’s slashing .301/.383/.609 with 33 homers, 95 RBI, 79 R, and 33 steals. I believe those stats are slightly inflated given the hitting environments he’s been in and the fact that he’s now 26 years old. However, they’re still interesting to note, especially following the injury to Mike Trout and the iffiness of Jo Adell in the majors. Overall in his 500+ games in the minors he’s hit .256 with 89 homers and 53 steals which means the bulk of his totals have come in the last two years. Cabbage might see a call-up with the injury to Trout and Anthony Rendon.

Robert Gasser — LHP Milwaukee Brewers

Back in late-May I wrote up Robert Gasser as a potential fill in for the Brewers rotation despite the rough ratios and walk rates. Now though, he’s figured things out at Triple-A Nashville. In the last 30 days, five starts, he’s posted a 2.90 ERA and 0.94 WHIP with a 35:5 K:BB ratio in 31 innings. That means that since late-May, the southpaw has taken about a run off of his ERA, FIP, and xFIP while also lowering his WHIP from 1.47 to 1.14 and cutting his BB/9 basically in half. The NL Central is still quite competitive and the Brewers could use help in the starting rotation in the second half. That’s where Gasser comes in. Combined with last year, the lefty has now spent 106.1 innings at Triple-A and his numbers this year are now better than last year’s intro to Nashville. Expect to see him called up some point in the next few weeks.

Jacob Lopez — LHP Tampa Bay Rays

We’re going very deep on this one. Jacob Lopez isn’t on anyone’s radar. Literally no one. However, Tampa keeps losing starters and has a very deep system in terms of arms. Over the last 30 days at Triple-A Durham, Lopez has started five games with 24.1 innings on the ledger. In those 24.1 innings he’s allowed five runs, with one earned, while striking out 28. Even if we count all five runs as earned, that’s still a sub-2.00 ERA in that span with a 1.01 WHIP. Lopez missed all of the 2022 season with injuries and didn’t pitch a full year in 2021 either. That being said though, he’s racked up 207.1 IP in the minors since 2018 with a 2.21 ERA, 1.02 WHIP, .196 BAA, and a 273:65 K:BB ratio. That works out to an 11.8 K/9 and 2.82 BB/9 for a guy who’s off the radar. There is a shot he comes up to bolster the injured pitching staff but he is likely to be on an innings limit this year since his 65.2 IP this year is already more than Lopez threw in 2021 (59.2 IP). Lopez profiles as a backend rotation arm.


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