Must-Add Waiver Wire Pickups for Week 4 Fantasy Baseball (2026)

April 20, 2026

Andy breaks down his must add fantasy baseball waiver wire pickups for Week 4 of the 2026 MLB season. Add these players now off the waiver wire and win more.

With another week of MLB action behind us, it's time to spotlight our top-7 must-add players ahead of Week 4 of the fantasy baseball season.

This week, we will spotlight several high-end power bats and two emerging starting pitchers who could provide major returns in the strikeout department. As a reminder, all players in this piece are currently rostered in less than 50% of all Yahoo leagues.

Be sure to follow RotoBallerMLB on X for all of our league-winning content and me, @A_Smith_FS, for any questions! Additionally, be sure to use code SMITH at checkout for 30% off on all premium packages. Let's dive in! Note - All statistics are updated as of Friday, April 17.

2026 Fantasy Baseball: Week 4 Waiver Wire Adds

Dillon Dingler, C, Detroit Tigers

The catcher to target on the waiver wire this week is Detroit's Dillon Dingler. Dinger has enjoyed a strong start to the 2026 campaign but is still widely available in most one-ctacher formats. Throughout 16 games, Dingler has played at a high level, posting a .283/.367/.566 slash line with three doubles, four home runs, and a 10:3 K:BB.

While his face-value metrics are impressive, his underlying marks suggest the 27-year-old could enjoy a career season.

Currently, the Ohio State product has generated an elite .485 xwOBA, .345 xBA, and a .732 xSLG, all of which place him in the 99th percentile among qualified hitters. Additionally, Dingler has impacted the ball at a high level, generating a 20.9% barrel rate, 60.5% hard-hit rate, and a 93.3 mph average exit velocity, all of which are well above the average marks.

While his hard-hit rates have kept his ceiling high, Dingler is also impacting the ball far more effectively than ever before, which has been the catalyst for his early-season production. Through the opening weeks, Dingler has generated an elite 46.5% LA Sweet-Spot% and a 33.3% squared-up rate, both of which are on pace to be the highest marks of his career.

The backstop has also generated a plus Pull AIR% (18.6%), which should keep his home run total stable, especially if he continues to impact the ball as hard as he has been.

Dingler provided a strong .278 AVG last summer but only went deep 13 times. However, given his drastic rise in power metrics, Dingler has the skill set to not only post an elite batting average but also go deep 20 times in 2026.

DESTROYED BY DING ‼️ pic.twitter.com/UZP5O7bi1p

— Detroit Tigers (@tigers) April 16, 2026

Jake Burger, 1B, Texas Rangers

The top option for power this week, especially in the infield, is Jake Burger. Burger is coming off a disappointing 2025 campaign, which pushed him into the final rounds of most drafts this spring. In 2025, Burger hit just 16 home runs, while posting a low .236/.269/.419 line. However, the summer before, Burger was one of the most potent sluggers in the game, launching 29 round-trippers with a .250/.301/.460 line.

Through the opening weeks of the 2026 campaign, Burger has looked like his 2024 self, as he has gone deep five times while carrying a .253/.278/.507 line. While the sample size is small, Burger has made the necessary adjustments to suggest this surge is quite sustainable.

The 30-year-old has generated a high .479 xSLG, 13.2% barrel rate, and a 50.9% hard-hit rate, all of which place him well above the average marks of qualified hitters. His 74.3 mph average bat speed also places him within the 73rd percentile among hitters.

However, the most important component of his profile behind his early-season power production is his Pull AIR%. Through 19 games, Burger has generated an elite 24.5% Pull AIR%, which is among the highest marks in the sport and is on pace to be the highest of his career. While this mark may not be sustainable, it is a massive jump from the 13.5% Pull AIR% he generated last summer.

Even a 6-8% incrase would put him back on pace to contend for a 25-HR campaign as he did in 2024. His counting stats should also benefit from his increase in power totals, especially batting in the cleanup spot on a daily basis.

Justin Crawford, OF, Philadelphia Phillies

While Crawford is not a reliable option for power, he is a priority target for those needing a boost in batting average and stolen bases. Though his first 17 MLB games, the rookie has held a solid .283 AVG but has posted a low .396 SLG. He has hit four doubles and added a triple, but has yet to go deep. He has also swiped one bag while carrying a solid 22.4% K%.

Last summer, Crawford spent his entire 2025 campaign with Triple-A Lehigh Valley and showcased similar high-end contact and speed skills. Across 112 games, Crawford held a .334/.411/.452 line with 23 doubles, seven home runs, and an impressive 46 stolen bases.

Throughout his time with the Phillies, Crawford has carved out a prominent role in center field but has been limited to the nine-hole, which has kept his counting stats low. However, given how his contact skills have translated to MLB pitching, the stolen bases should begin to climb as he grows more accustomed to the majors.

While Crawford should not be a priority target for those lacking power and RBI, managers needing a sneaky asset for a high batting average and stolen bases should look to target Crawford before he begins to showcase his speed in Philadelphia.

Mickey Moniak, OF, Colorado Rockies

The final hitter we will spotlight this week has the opposite skill set of Crawford, an outfielder who can provide you with home runs and RBI. Moniak missed the start of the regular season due to a minor finger injury, but has immediately reclaimed his fantasy value and is quickly entering must-roster territory.

Through his first 13 games, Moniak has gone deep five times and tallied six runs and nine RBI. During this stretch, Moniak has held a solid .256 AVG. Even though the slugger is in a platoon (albeit on the strong side), Moniak carries solid OF4/OF5 value in all standard formats ahead of Week 4.

Last summer, Moniak turned in a career season in his debut campaign with the Rockies, going deep 24 times with a .270 AVG. Throughout the early going, Moniak has continued to generate high-end power metrics, suggesting he should remain an above-average contributor in the power department. The 27-year-old has placed in the 86th percentile in xSLG with a 12.5% barrel rate.

Like Dingler and Burger, Moniak has also begun to hit the ball far more effectively (for power) as evidenced by his 31.3% Pull AIR%. While this mark is unlikely to remain stable over the summer, even if it drops a few points, Moniak will still see his power numbers remain elite, especially when playing half his games at Coors Field.

Two at-bats, two home runs for Mickey Moniak 😤 pic.twitter.com/thRnXDd9u9

— MLB (@MLB) April 12, 2026

Mick Abel, SP, Minnesota Twins

Mick Abel saw his fantasy value spike in spring training, but a slow start sent him to the waiver wire in most standard leagues. However, Abel has turned in back-to-back dominant outings and is emerging as a must-starter starting pitcher. Over his first two outings of the season, Abel allowed nine runs over 7 1/3 innings while striking out just seven hitters.

In his last two outings, Abel has logged 13 straight shutout frames with 16 punchouts, with just three walks and eight hits. In his last start, he totaled a career-best 10 punchouts.

Abel has leaned on his four-seamer (42.9% usage) and has been a major asset in generating whiffs. Through four outings, this pitch posted a high 33.8% whiff rate. However, it has generated a rough .480 xwOBA, which suggests he should see some regression in his ratios. His No. 2 pitch, his changeup, has been elite, boasting a 31.3% whiff rate with a stellar .264 xwOBA.

In 2025, he threw this pitch just 8.8% of the time, but it has developed into his true No. 2 option in 2026, which can be the driving force behind his breakout. While he has not thrown it as often as he did last season, his curveball has remained very effective, generating a low .217 xwOBA with a 19.0% whiff rate.

His overall 67% whiff rate suggests his strikeout numbers should remain high. While he may face some regression as his fastball is still quite hard, he should remain an above-average contributor when looking for strikeouts.

It's a 10-strikeout night for Mick Abel 💪 pic.twitter.com/s8jbIRGNa9

— MLB (@MLB) April 15, 2026

Spencer Arrighetti, SP, Houston Astros

The other starting pitcher we are spotlighting this week is Spencer Arrighetti of the Houston Astros. Arrighetti made his MLB debut back in the 2024 season and tossed 145 innings with a 4.53 ERA and a modest 1.41 WHIP. He struck out an impressive 171 hitters, but his 10.3% BB% kept his fantasy value inconsistent.

In 2025, Arrighetti logged only 35 1/3 innings in the majors as he battled numerous injuries. In 2026, he began the campaign with Triple-A Sugar Land, but following several injuries to the MLB roster, the Astros turned back to Arrighetti to make a spot-start. The right-hander did not disappoint in his MLB return, as he logged six innings of one-run ball with three hits, four walks, and 10 punchouts against the Colorado Rockies.

In this outing, Arrighetti's curveball led the way, generating an elite 72.7% whiff rate with a .063 xwOBA. In 2024, Arrighetti's cruvbeall was just as sharp, generating a 42.4% whif rate with a .211 xwOBA. While Arrighetti only threw his four-seamer 16.0% of the time (which would be the lowest of his MLB career), it was not overly effective back in 2024, so leaning more on his curveball should generate better results.

In 2024, Arrighetti's four-seamer generated a modest .369 xwOBA but held a solid 19.9% whiff rate. Another pitch to monitor is his sweeper, which posted a 38.6% whiff rate back in 2024 and was deployed 17.0% of the time in his first outing in 2025. His sweeper and elite curveball should keep his strikeout totals in the high-end range.

Earlier this season, prior to his MLB promotion, Arrighetti was looking just as dominant at Triple-A, striking out 20 hitters over 14 1/3 innings (with a 1.26 ERA). With several starting pitchers on the shelf in Houston, including Hunter Brown, Tatsuya Imai, Cody Bolton, and Cristian Javier, Arrighetti should remain locked into a starting job for the foreseeable future.

Bryan Baker, RP, Tampa Bay Rays

Rounding out our list will be the potential new closer in Tampa Bay. While Griffin Jax opened the campaign as the favorite, his slow start to the season pushed him to a low-leverage role, which opened the door for Baker to emerge, especially with Edwin Uceta and Garrett Cleavinger both off the shelf.

Through 7 1/3 innings this season, Baker has tallied four saves with three earned runs and a 7:2 K:BB. This week, Baker earned two saves for the Rays (April 14 and April 16) and allowed just one base runner in both outings combined.

Under the hood, the 31-year-old has posted a promising 2.65 xERA and .212 xBA, both of which are well above average. Additionally, Baker has posted an elite 38.9% whiff rate, suggesting higher strikeout totals are on the way, as his low 24.1% K% does not correlate with this elite mark. He has also posted an above-average 6.9% BB%, which should keep his WHIP low.

While Uceta's eventual return and Jax's recent improved play (four-straight shutout frames entering Friday) do make his seat warm, Baker has emerged as the leader in this bullpen. Managers falling behind in saves should prioritize him on the waiver wire.

Other Waiver Wire Targets

• Carter Jensen, KC
• Colt Keith, DET
• Jeremiah Jackson, BAL
• Owen Caissie, MIA
• Landen Roupp, SF
• Kyle Harrison, MIL
• Joel Kuhnel, ATH

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