Buy Low, Sell High Fantasy Baseball Trade Advice for Week 9 (2026)

May 27, 2026

Joey's fantasy baseball buy low, sell high trade advice for Week 9 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 9 of the 2026 season, highlighting the best players to trade for and trade away. If you are brand new to this weekly series, we look at the best players to buy and sell each week of the fantasy baseball season. 

For this week, we will dive into three buy-low candidates and two sell-high candidates. All three buy-low players on this list have struggled to produce solid numbers recently, but better days are ahead for all three players. The two sell-high players are currently overperforming on the mound, and some negative regression is headed their way.

So, which players should fantasy managers buy and sell for Week 9 of the fantasy baseball season? Let's dive in and find out.

Undervalued Fantasy Baseball Players to Trade For

Nolan McLean, SP, New York Mets

Fantasy managers were on top of the world when New York Mets starting pitcher Nolan McLean threw six innings of one-run ball against the Diamondbacks on May 8. That outing lowered his ERA to 2.78 on the season, and McLean was looking like a top fantasy pitcher. Unfortunately, the rookie has hit a wall in recent weeks.

He allowed nine runs (six earned runs) on eight hits across 5 2/3 innings against the Nationals on May 19 and then gave up seven runs on five hits across 3 1/3 innings against the Reds in his most recent start on Monday. Following these two poor outings, McLean now owns a 4.40 ERA and a 6.92 ERA in the month of May.

Nolan McLean on the issues in his past two starts:

"Combination of things. Getting behind in counts, not landing my off-speed pitches like I should, and I've been hitting guys with two strikes too which isn't a great recipe for success" pic.twitter.com/yimaJ7fl6R

— SNY (@SNYtv) May 25, 2026

This recent stretch from the Mets right-hander gives fantasy managers the perfect opportunity to buy him in all formats. Despite allowing 13 earned runs over his last two starts, McLean is an easy buy-low target. His expected ERA (2.92) is 148 points less than his actual ERA (4.40), and his expected batting average against (.214), average exit velocity (87.2 mph), and strikeout rate (29.5%) all rank pretty well.

Things might not be great for McLean right now, but he will pitch better in the coming weeks. He still possesses a low WHIP (1.09) and has struck out 75 batters across 61 1/3 innings pitched this season. He's an easy buy.

Mookie Betts, SS, Los Angeles Dodgers

There are a lot of managers frustrated with Los Angeles Dodgers shortstop Mookie Betts' production in the early going. He spent almost one month on the injured list due to an oblique strain earlier in the year and is currently slashing .165/.230/.342 with four home runs, two doubles, and 10 RBI across 20 games this season. After a down offensive year in 2025, the best may be behind Betts.

However, the eight-time All-Star will eventually turn things around at the plate. He's too talented not to, and his metrics suggest he'll be a better fantasy option moving forward. His .267 expected batting average is 102 points higher than his actual batting average (.165), and his expected slugging (.459), launch angle sweet-spot rate (42.4%), squared-up rate (46.2%), and barrel rate (10.6%) are all up from last year.

It's still too early in the season to say that Betts is washed. He has played in just 20 contests this year and is still working to get into a groove at the plate. Don't forget, the 33-year-old played in just eight games before landing on the 10-day IL on April 5. Give him a chance to heat up. That's exactly why the Dodgers shortstop is a must-buy in all formats.

Better days are surely ahead for the former American League MVP.

Kazuma Okamoto, 3B, Toronto Blue Jays

Toronto Blue Jays third baseman Kazuma Okamoto is currently in a rough slump at the plate. He has just four hits over his last 42 at-bats (.095 batting average) to go with two doubles, one RBI, and 20 strikeouts dating back to May 12. This cold offensive stretch has made Okamoto one of the most traded players in Yahoo! leagues at the start of Week 9.

There's a reason so many fantasy managers are willing to trade for Okamoto despite his recent offensive numbers. The last time he went through a slump, he eventually bounced back. The Blue Jays third baseman hit .143 with one home run and five RBI from April 8 to April 21. He then proceeded to hit .308 with seven home runs and 18 RBI in his next 18 games from April 22 to May 11.

Kazuma Okamoto extends his hitting streak to 10 games 👊 pic.twitter.com/CBeHaNazde

— Sportsnet (@Sportsnet) May 11, 2026

Okamoto is one of the best power bats to acquire for cheap in fantasy right now. He has a 95th percentile average exit velocity (93.2 mph), an 89th percentile barrel rate (14.9%), a 95th percentile hard-hit rate (52.9%), and an elite 24.8% Pull AIR rate. All those metrics prove that the 29-year-old will return to being a strong fantasy option within the next few weeks.

Overvalued Fantasy Baseball Players to Trade Away

Merrill Kelly, SP, Arizona Diamondbacks

Arizona Diamondbacks starting pitcher Merrill Kelly has been dealing on the mound recently. He has a 2.17 ERA over his last four starts and just threw seven innings of two-run ball with four strikeouts against the Giants on Monday evening. During this stretch, Kelly also threw a complete game against the Rockies by tossing nine innings of one-run ball back on May 15.

Merrill Kelly finishes his first career complete game with a strikeout!

(MLB x @Abbvie) pic.twitter.com/zWNSb0KZpC

— MLB (@MLB) May 16, 2026

There's no denying how impressive the veteran has been in his last few outings. He has dropped his ERA by 470 points (from 9.95 to 5.25) in these four starts, and has seen his rostership in Yahoo! leagues increase to over 50%. However, Kelly is the perfect sell-high candidate in Week 9 of the fantasy baseball season.

For starters, the Diamondbacks right-hander faced the Mets, Rockies, and Giants (twice) during this four-start stretch. All three of those teams rank in the bottom 10 in runs per game this season. Additionally, his metrics are quite concerning. His expected ERA (8.21), expected batting average against (.330), and barrel rate (18.4%) all rank in the bottom 1% of the league.

Kelly simply won't be pitching this well the rest of the season. He has a bottom 10% strikeout rate (14.9%), and his hard-hit rate (45.6%) ranks in the 14th percentile. Trade him now while his fantasy value is so high.

Nick Lodolo, SP, Cincinnati Reds

Cincinnati Reds starting pitcher Nick Lodolo finally looked like his former self in his most recent outing against the New York Mets. After starting the season on the 15-day injured list and struggling in his first few starts, Lodolo had his best outing of the season on Monday. He tossed six innings of one-run ball with six hits, no walks, and a season-high seven strikeouts.

Lodolo always has the potential to be a really good fantasy option. He finished with a 3.33 ERA and a 24.3% strikeouts across 156 2/3 innings last year and was one of the top rookies in the National League back in 2022. But following his strong performance on the mound against the Mets, it's best to sell him high.

Injuries continue to hold back Lodolo from reaching his full potential. He already spent time on the injured list to begin the year due to a blister issue and has pitched under 120 innings in three of his first four Major League seasons. There are just too many injury concerns with the 28-year-old to trust him as a solid fantasy option throughout the 2026 season.

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