MLB Prospect Debuts: Fantasy Baseball Waiver Wire Pickups and Rookie Stashes (Week 10)

Fantasy Baseball Hitter Prospects To Target

Edwin Arroyo, 2B/SS, Cincinnati Reds (15% rostered)

Level: MLB

2026 Stats: 250 PA, .323/.383/.562, 41 R, 11 HR, 34 RBI, 9 SB, 7.2% BB%, 16.8% K%, 143wRC+

Over the weekend, Reds two-time All-Star shortstop Elly De La Cruz suffered a hamstring injury and was placed on the 15-day injured list. In a corresponding move, Cincinnati called up its No. 17 prospect, Edwin Arroyo.

Arroyo is a 22-year-old switch-hitting shortstop from Puerto Rico whom the Reds acquired from the Mariners in the trade that sent Luis Castillo to Seattle. After a strong start to his minor league career, Arroyo suffered a shoulder injury that sidelined him for the entire 2024 season.

Since then, questions have lingered about his power potential. In 2025, those concerns appeared justified, as he hit just three home runs across 521 plate appearances. However, his shoulder issues now seem to be behind him.

At Triple-A this season, he has posted a .448 expected slugging percentage (xSLG) and recorded a career-high max exit velocity of 109.1 mph.

With his power still developing, Arroyo’s bat should be good enough to hold its own at the major league level, but what will really keep him in the lineup is his defense. He wasted no time showing that upside when he flashed some leather in his MLB debut.

A slick play by Edwin Arroyo at second base for the @Reds! pic.twitter.com/FGyv7TPfws

— MLB Pipeline (@MLBPipeline) June 1, 2026

Right now Arroyo is starting at second base, with Matt McLain shifting over to shortstop. Although, once De La Cruz returns, the Reds coaching staff has indicated that Arroyo will primarily serve in a utility role.

But with that said, it's not hard to envision Arroyo taking over as the team's starting second baseman before long.

Cincinnati is currently giving McLain regular starts at the keystone, but he has struggled throughout the season, posting a 75 wRC+ across 226 plate appearances.

If Arroyo sees regular playing time for the rest of the season, he projects for up to eight home runs, 10 stolen bases, and a .260 batting average. Overall, he’s worth a pickup in 15-team leagues as a middle infield option with some upside.

Joshua Baez, OF, St. Louis Cardinals (12% rostered)

Level: Triple-A

2026 Stats: 226 PA, .249/.332/.557, 38 R, 16 HR, 39 RBI, 11 SB, 7.6% BB%, 31.7% K%, 123 wRC+

If you’ve followed this article throughout the season, then you know Joshua Baez’s fantasy upside. Now, the Cardinals’ No. 7 prospect is making a strong case for a promotion to the majors.

Over his last 10 games at Triple-A, Baez has launched five home runs while adding two doubles, two triples, three stolen bases, and a .333 batting average.

The 22-year-old offers an exciting blend of power and speed, and the underlying numbers in Triple-A back up that claim. Baez owns a 20.2% barrel rate and a 51.9% hard-hit rate, along with elite sprint speed.

Here’s a look under the hood.

The biggest concern is his plate discipline. He’s striking out at nearly a 32% clip and has one of the highest chase rates in Triple-A. To make matters worse, he doesn’t walk much either, which makes his 2026 projections fairly volatile.

So, when should we expect Baez in the majors? It should be very soon, especially if St. Louis is serious about staying in the Wild Card race. Coming into the season, Baez was expected to be called up early with the rebuilding Cardinals likely out of contention.

Instead, they’ve stayed in the race, and now it feels like he could be promoted soon to help push for a playoff spot. For fantasy managers, Baez is worth stashing in deeper leagues, especially 15-team formats with five outfield spots.

Once he gets the call to the majors, he should be rostered in most leagues because of his immense upside. Just be sure to keep an eye on his strikeout rate, as that will likely determine how much immediate fantasy value he will provide.

Ryan Ward, OF, Los Angeles Dodgers (1% rostered)

Level: MLB

2026 Stats: 214 PA, .254/.379/.418, 28 R, 6 HR, 31 RBI, 6 SB, 15.9% BB%, 20.1% K%, 110 wRC+

The Los Angeles Dodgers called up corner outfielder Ryan Ward after Teoscar Hernandez was placed on the 15-day injured list with a left hamstring strain. Hernandez is expected to miss at least a month.

Ward is a power-first bat, and his fantasy value will mostly depend on playing time. Even so, he has already shown what he can do at the plate in just his third MLB game.

Fantasy Baseball Pitcher Prospects To Target

River Ryan, SP, Los Angeles Dodgers (13% rostered)

Level: Triple-A

2026 Stats: 22.0 IP, 2.05 ERA, 0.91 WHIP, 33.0% K%, 3.4% BB%, 2.00 FIP

Earlier this season, we highlighted Dodgers No. 5 prospect River Ryan. After another dominant Triple-A outing, it feels like it’s only a matter of time before he gets the call to the majors.

River Ryan continued his dominance of AAA with 6.0 shutout innings with 8 Ks yesterday

The Dodgers top pitching prospect is fully built up after returning from TJS earlier this season and is patiently waiting for his return to the Dodgers rotation. He looks so good! pic.twitter.com/usyu8upGXL

— Thomas Nestico (@TJStats) May 29, 2026

Over his last two starts, he has racked up 15 strikeouts with zero walks and no earned runs across 11 innings. Ryan is a power right-hander with a true starter’s arsenal.

He has a mid-to-upper 90s fastball that he pairs with a sharp slider that generates whiffs against both righties and lefties. He also mixes in a usable curveball, sweeper, and changeup to keep hitters off balance.

The biggest question for Ryan is how he is going to crack the Dodgers' starting rotation.

Even with Tyler Glasnow and Blake Snell on the injured list, the Dodgers are getting solid starts from Eric Lauer, Justin Wrobleski, and Roki Sasaki, so it may take another injury or rotation change for Ryan to get the call.

However, when he does arrive, he’s worth rostering in all formats. For now, he’s a strong stash in 15-team leagues, especially if you want to avoid having to spend big FAAB later.

The Athletics have called up their No. 2 prospect, Gage Jump, and he’s already shown the ups and downs that come with his game.

After a rough MLB debut against the Seattle Mariners, where he allowed four earned runs on nine hits and one walk across five innings, he bounced back with a dominant outing against the Chicago Cubs in his second start.

Gage Jump retires his last 14 batters en route to his first big league win 🐘

MLB's No. 40 prospect (@Athletics) logs 5 K's over 7 innings of one-run ball: https://t.co/vaDuDIIg59 pic.twitter.com/zlPBWpflmn

— MLB Pipeline (@MLBPipeline) June 3, 2026

Overall, he owns a 3.75 ERA and a 2.41 FIP with 10 strikeouts and just two walks across 12 MLB innings. For his arsenal, the 6-foot left-hander works with a mid-to-upper-90s fastball and mixes in a plus slider and curveball.

He also throws a changeup and a sweeper. All of his pitches posted over a 30% whiff rate in Triple-A this season. So what should we expect from Gage moving forward?

OOPSY, which incorporates Stuff+ and Statcast data, projects him for a 3.98 ERA and a 1.29 WHIP with a 24.5% strikeout rate and an 8.9% walk rate.

With that in mind, plus the hitter-friendly conditions at Sutter Health Park, Jump is best used in favorable matchups. Luckily for him, he has a couple of pitcher-friendly opponents on the horizon.

In his next start, he’ll take on the Astros in Houston, followed by two home starts against the Colorado Rockies and the Los Angeles Angels. He’ll then face the San Francisco Giants on the road at spacious Oracle Park.

You may want to sit him against the Astros, but after that, he becomes a solid option with plenty of upside in 12-team leagues.

More Fantasy Baseball Prospects and Rookies