Buy Low, Sell High Fantasy Baseball Trade Advice for Week 8 (2026)

May 19, 2026

Joey's fantasy baseball buy low, sell high trade advice for Week 8 of 2026. His undervalued fantasy baseball trade targets and overvalued players to trade away.

Welcome, RotoBallers, to our weekly buy/sell fantasy baseball trades advice article for Week 8 of the 2026 season, highlighting the best players to trade for and trade away. If you are new to this weekly series, we look at the best players to buy and sell each week of the fantasy baseball season. 

In this week's edition, we'll look at five of the best trade candidates. The three buy-low players on this list have all failed to meet fantasy expectations in recent weeks, but each of them should be a better all-around fantasy option moving forward. One of the players you should sell is overperforming, while the other is someone you should try to trade away amid a rough start.

So, which players should fantasy managers buy and sell for Week 8 of the fantasy baseball season? Let's find out.

Undervalued Fantasy Baseball Players to Trade For

Bo Bichette, 3B/SS, New York Mets

It's only a matter of time until New York Mets infielder Bo Bichette turns things around offensively. Bichette is off to a brutal start to begin his Mets tenure, as he is slashing .219/.273/.297 with three home runs, 21 RBI, and one stolen base across 47 games. But his metrics suggest he has been a bit unlucky at the plate in 2026.

Bichette entered the week with an expected batting average (.278) that was 68 points higher than his actual batting average (.210), and an expected slugging (.399) that was 130 points higher than his actual slugging (.269). Both that 68-point batting average difference and 130-point slugging difference were the fifth-worst differences among all hitters in baseball. That's a clear sign that Bichette's numbers should eventually improve.

BO! pic.twitter.com/qhPktcEL9F

— New York Mets (@Mets) May 19, 2026

Additionally, Bichette has hit the ball well in the early going. He ranks in the 64th percentile in average exit velocity (90.2 mph), 64th percentile in hard-hit rate (43.5%), 80th percentile in squared-up rate (29%), and 86th percentile in whiff rate (17.1%). It sometimes takes hitters some time to get comfortable on new teams, which could be happening here with the two-time All-Star.

He just went 3-for-6 with one home run and three RBI in Monday's win over the Nationals, so trade for him now before his numbers continue to climb.

Sal Stewart, 1B/2B/3B, Cincinnati Reds

Cincinnati Reds rookie Sal Stewart came out of the gate red hot. He was slashing .303/.398/.626 with nine home runs, 29 RBI, and seven stolen bases in his first 27 games and was emerging as a fantasy superstar. Since then, though, Stewart has cooled off significantly at the plate. The 22-year-old is batting a mere .186 with two home runs, three RBI, three stolen bases, and 18 strikeouts dating back to April 30.

Regression was always inevitable for Stewart following his hot start. He was on pace for 54 home runs, 174 RBI, and 42 stolen bases after his first 27 games. But this recent cold stretch gives fantasy managers the perfect opportunity to trade for one of the most exciting rookies in the game. He will eventually return to being a dominant fantasy option, and his metrics back that up.

Stewart has a .376 xwOBA, a .267 expected batting average, a .511 expected slugging, a 90.5 mph exit velocity, and a 17.2% barrel rate. All five of those metrics currently rank in the top 30% of the league. So, see what it would take to acquire the Reds rookie. Being in a current 4-for-21 slump could make him more available in trade talks.

Logan Gilbert, SP, Seattle Mariners

Seattle Mariners starting pitcher Logan Gilbert was viewed as a safe selection in fantasy drafts this spring. He has been a workhorse on the mound since he entered the league and has emerged as a fantasy ace in recent seasons. Last year, Gilbert finished with a 3.44 ERA, a 1.031 WHIP, and a career-high 32.3% strikeout rate across 131 innings pitched.

However, that same pitcher has not shown up in the early portion of the 2026 campaign. The tall right-hander has a whopping 4.45 ERA across his 10 starts and is coming off his worst outing of the year his last time out. Gilbert allowed a season-high seven runs against the San Diego Padres on Saturday, which marked the first time he has given up this many runs in a start since July 29, 2024.

Despite his poor numbers to start the season, Gilbert is the best buy-low target at the position right now. He's still getting a lot of swing-and-miss on his pitches with a 32.2% chase rate and a 28.9% whiff rate, and just had a dominant performance against the White Sox two starts ago when he threw six shutout innings with nine strikeouts on May 10.

Logan Gilbert, Wicked 86mph Slider. 🤢 pic.twitter.com/sR9RfJ59TM

— Rob Friedman (@PitchingNinja) May 5, 2026

Trust Gilbert's track record and buy low on one of the most consistent pitchers in the game. It'll pay off.

Overvalued Fantasy Baseball Players to Trade Away

Michael Soroka, SP, Arizona Diamondbacks

Arizona Diamondbacks pitcher Michael Soroka has thrown the ball really well to start the 2026 season. Outside of an eight-run clunker against the Brewers last month, Soroka has been a consistent fantasy option. He has a 3.49 ERA and 55 strikeouts across 49 innings pitched and has allowed two runs or fewer in seven of his nine outings this season.

Michael Soroka, Nasty 83mph Slurve...and Sword. ⚔️ pic.twitter.com/BiAa8oU6Vq

— Rob Friedman (@PitchingNinja) April 23, 2026

The reason why Soroka is a sell-high candidate, though, is because some negative regression is headed his way in the coming weeks. His expected ERA (4.76) is 127 points higher than his actual ERA (3.49), and his expected batting average against (.273), average exit velocity (90 mph), and barrel rate (10.1%) all rank in the bottom half of the league.

While Soroka has looked really good on the mound, his inevitable regression makes him a sell in all formats. His fantasy value might never be higher, and it's hard to see him keeping this up with a fastball that averages just 93.7 mph. He also continues to allow a lot of contact in the air on the pull side, as opposing hitters have a 20.3% Pull AIR rate this season. So, trade him away now before his fantasy value decreases.

Salvador Perez, C/DH, Kansas City Royals

Kansas City Royals catcher Salvador Perez has gotten off to a slow start this year. He's batting only .201 with seven home runs and 20 RBI across 193 plate appearances and is finally showing signs of decline in his age-36 season. His bat speed (71.3 mph) is down 1.6 mph from last year (72.9 mph), which could be a telling sign that it's all downhill for Perez.

Instead of buying low on one of the best-hitting catchers of this generation, it's best to sell Perez for whatever you can get at this point. Based on name value alone, there's a chance you could get a solid player in return.

All signs point to Perez really taking a step back offensively in his 15th Major League season. He ranks in the 11th percentile in xwOBA (.273), 15th percentile in expected batting average (.213), 37th percentile in expected slugging (.375), 27th percentile in squared-up rate (22%), and ranks dead last in chase rate among all qualified hitters (46.4%). Those metrics are all massively down from the 2025 season.

There is someone in your league who might still believe in Perez. He just hit 30 long balls last year and has tallied 100+ RBI in consecutive seasons for the first time in his career. However, it's clear the best is behind him. The Royals catcher will have a hard time being a viable fantasy option with those metrics above.

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