Overvalued, Undervalued Trade Targets - Buy/Sell for Fantasy Baseball (Week 7)

May 11, 2023

Trade candidates to buy or sell in fantasy baseball after Week 7 of the 2023 MLB season. Ben Rosener lists overvalued and undervalued players to target or trade away.

Making the right trades can be crucial to championship success in fantasy baseball. Almost as much as the draft, if not more. While most trades can have a significant impact on your fantasy team, it’s the deals where you acquire undervalued players and then see their production improve that can really tip the scales in your favor where the standings are concerned.

The same can certainly be said about trading away players at the right time when they have the most fantasy trade value. Those deals could happen in the second week of April or the last week of August, but they’re impactful all the same.

Here are some undervalued candidates to pursue in trades and some overvalued ones who you should consider dealing for if they presently occupy a spot on your roster.

Undervalued Players To Trade For

Michael Harris, Atlanta Braves

Harris missed time earlier this season due to a stint on the injured list with a lower back strain, so his sample size of plate appearances isn’t quite as large as it could be.

In 55 plate appearances this season as of the start of play on Wednesday, the outfielder is batting .208 with a .309 on-base percentage, a home run, and three stolen bases.

At face value, it’s not an ideal set of metrics for a player who had a breakout rookie season, batting .297 with a .339 on-base percentage, 19 home runs, and 20 stolen bases in 441 plate appearances. The 22-year-old also added the following metrics, making plenty of quality contact.

• .335 xwOBA
• 10.1% barrel rate
• 44.8% hard-hit rate
• 24.3% strikeout rate
• 4.8% walk rate

But Harris’ underlying metrics, at least in a small sample size so far, show a significant improvement over last year’s metrics.

Again, we’re still dealing with fewer than 60 plate appearances, but there’s a lot to like about Harris’ underlying metrics so far:

• .354 xwOBA
• 15.8% barrel rate
• 55.3% hard-hit rate
• 18.2% strikeout rate
• 10.9% walk rate

What’s more, Harris is also hitting the ball in the air more -- his ground ball rate has dropped from 55.8% last year to 50% this year and his fly ball rate has spiked from 17.9% to 28.9% -- with more barrels. He’s also striking out less so far and drawing walks at a higher rate.

In most instances, some combination of those are hallmarks of a player taking a step forward at the plate. But Harris is doing all of them at the moment. And while it still is a smaller sample size, Harris looks destined for some positive regression in the near future at worst. At best, he could have an even more impactful season than his rookie campaign -- from here on out that is.

Mitch Keller, Pittsburgh Pirates

Keller isn’t exactly the most undervalued fantasy pitcher at the moment, not after throwing a complete game, four-hit shutout in his last start.

Overall, the right-hander has pitched to a 2.72 ERA and a 3.02 FIP in 49.2 innings this season for the resurgent Pittsburgh Pirates. He has logged four pitcher wins in his eight starts and added 56 strikeouts compared to just 14 walks and four home runs allowed.

He’s been particularly effective in his last four starts, logging a 1.73 ERA and a 1.51 FIP in 26 innings while adding 10.73 strikeouts per nine frames compared to just 1.38 walks surrendered per nine frames.

Perhaps most crucially in that stretch -- which has also included three pitcher wins -- is the fact that Keller is limiting hard contact at an elite rate, with just a 31.8% hard-hit rate and an average exit velocity of 87.3 mph during that span.

For the season, opponents have managed just a 27.3% hard-hit rate against the Pirates ace, which sits in the 93^rd percentile league-wide.

Speaking of percentile rankings, Keller ranks in the 62^nd percentile or better in all of the following categories in addition to hard-hit rate: chase rate (62^nd), walk rate (64^th), xSLG (66^th), xBA (70^th), xwOBA (75^th), and average exit velocity (88^th).

Elsewhere, he entered play on Wednesday with the 14^th-best Stuff+ (105) among qualified starters and the joint eighth-best Pitching+ (105) among the same group.

Everything here screams “legitimate” in terms of Keller’s ability, effectiveness, and fantasy ceiling.

However, perception can sometimes be everything. If someone in your league doesn’t think the breakout is real for Keller and thinks it might be fluke-like for a starter with a career 4.70 ERA and 3.96 FIP, now might be the time to make a move.

Overvalued Players To Trade Away

Starling Marte, New York Mets

In the past, Staring Marte has generally been productive despite low hard-hit rates. A combination of high BABIP metrics and low strikeout rates certainly helps in that regard, but the outfielder has hit at least .280 in each of the last four seasons despite posting respective hard-hit rates of 38.6%, 30.3%, 39.6%, and 33.9%, respectively.

Starling Marte In The Last Four Seasons:

• 2019: 586 PA, .295 average, .362 xwOBA, 38.6% hard-hit rate, .319 BABIP
• 2020: 250 PA, .281 average, .326 xwOBA, 30.3% hard-hit rate, .319 BABIP
• 2021: 526 PA, .310 average, .347 xwOBA, 39.6% hard-hit rate, .372 BABIP
• 2022: 505 PA, .292 average, .336 xwOBA, 33.9% hard-hit rate, .340 BABIP

This season, however, his hard-hit rate has fallen to 31.1%, his lowest in a full season since the 2017 campaign. And it’s not just the hard-hit rate either, Marte simply isn’t doing as much damage when he is making contact. He has a .338 xwOBAcon that is on track to be his lowest in a season in any of the last nine campaigns. For reference, Marte’s xwOBAcon has finished below the .370 mark just once in a full season since the start of the 2015 campaign.

Add in a .273 BABIP that is low to begin with and nearly .070 points below his career .342 BABIP, and you have an unideal combination where Marte’s production is concerned.

With that in mind, it shouldn't be a surprise that the veteran is batting just .223 with a .298 on-base percentage and a home run in 125 plate appearances this season.

With his ability to steal bases -- the outfielder has nine so far -- and a regular place in the New York Mets’ lineup, there’s still some fantasy value and upside to be had here. The stolen bases and the place in the Mets' lineup are exactly why now is the time to trade the veteran outfielder.

With stolen bases up league-wide, thus negatively impacting the value of fantasy players who primarily provide stolen base production, it’s possible to replace Marte’s production via the waiver wire or simply with the other players in your starting lineup.

What’s more, if another manager is willing to part with a significant fantasy contributor for Marte while banking on a potential rebound and his past success, it might be prudent to trade the Mets outfielder now. Because unless he suddenly starts getting more fortunate with his BABIP, there just isn’t enough in his underlying metrics to suggest that a major bounce-back is on the horizon this season.

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