Overvalued, Undervalued Trade Targets - Buy/Sell for Fantasy Baseball (Week 5)

Trade candidates to buy or sell in fantasy baseball after Week 5 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.

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Undervalued Players To Trade For

J.D. Martinez, Los Angeles Dodger

Martinez is enjoying a strong season in Los Angels with the Dodgers, though his surface-level numbers don’t necessarily suggest it. The veteran designated hitter is batting .250 with a .306 on-base percentage and four home runs in 98 plate appearances for the National League West club this season.

While those metrics don’t exactly jump off the page, it’s his quality of contact numbers that should be the key driving force behind some positive regression. Martinez has logged a 15.0% barrel rate – on track to be his best since 2018 – to go along with a .571 xSLG, a .538 xwOBAcon, and a 49.2% hard-hit rate so far. Elsewhere, he’s turned in a quality wOBA (.353) with an even better xwOBA (.386).

All told, at the beginning of play Wednesday, Martinez ranked in the 84^th percentile in each of the following statistical categories league-wide: barrel rate, xwOBA, hard-hit rate, xBA, xSLG, and average exit velocity. Perhaps unsurprisingly, due to all that loud contact, the former Tiger’s ISO is up exactly .100 points this season, rising from .174 to .274.

The veteran should also continue to benefit from regular home games at Dodger Stadium. In home games this season, Martinez owns a .344 wOBA, a .261 ISO, and a .800 OPS – not to mention an expected home run number of seven at his new home ballpark.

That he’s primarily a designated hitter and thus confined to utility spots in fantasy leagues limits his fantasy ceiling to a degree, but it only seems like a matter of time before his production at the plate takes off even more.

Corbin Burnes, Milwaukee Brewers

First and foremost, Burnes’ strikeouts are down so far this season. He’s striking out 7.16 batters per nine innings and owns a 19.5% strikeout rate. The 28-year-old’s swinging strike percentage is down to 11.0% while his whiff rate is at 26.1%. All four metrics would be career lows for Burnes as a starting pitcher if the season ended today.

Thankfully, the season doesn’t end today and there’s plenty of room for Burnes to bounce back from those strikeout numbers, not to mention a 4.55 ERA and a 4.45 FIP. In short, it’s the perfect time to try and acquire the fantasy ace.

Despite some of the struggles and the decrease in most bat-missing stats, Burnes’ stuff is still grading out as elite and hasn’t dropped too much all things considered. After logging a 126 Stuff+ number last year, the second-best among all qualified starters, Burnes is currently sporting a 118 Stuff+ metric. It’s obviously a bit lower than last year’s number but still sits inside the top 10 among qualified starters so far during the young season.

Elsewhere, his Location+ and Pitching+ numbers aren’t incredibly far off either.

Corbin Burnes In 2022*:

• 126 Stuff+
• 102 Location+
• 109 Pitching+

Corbin Burnes In 2023*:

• 118 Stuff+
• 100 Location+
• 107 Pitching+

*Data via FanGraphs.

While his run-prevention numbers don’t look like anything to write home about, the former Cy Young winner has been decidedly more effective after a pair of rough starts to begin the year.

Following a two-start stretch in which he allowed 11 hits, 10 earned runs, five walks, and two home runs – compared to eight strikeouts – in 9.1 innings, Burnes fired off eight shutout innings against the Arizona Diamondbacks, scattering just three hits while striking out eight.

Overall, he’s pitched to a 1.96 ERA and a 3.11 FIP in his last three starts spanning 18.1 innings. During that time he’s struck out 16 batters compared to five walks and has logged two pitcher wins.

Overvalued Players To Trade Away

Elias Diaz, Colorado Rockies

Diaz is batting .333 with a .392 on-base percentage, two home runs, and a .386 wOBA in 75 plate appearances. He’s also added a 43.9% hard-hit rate and is striking out just 19% of the time. That’s the good news. The veteran has also provided some quality early-season production to Colorado Rockies and fantasy managers alike.

He’s been particularly helpful for fantasy managers who’ve had to navigate early-season injuries to the likes of Will Smith, Logan O’Hoppe, and Mitch Garver. The not-so-good news is that Diaz’s production might not be all that sustainable. Despite the hard-hit rate and relatively low strikeout rate, there’s potential regression on the horizon here.

The .400 BABIP is obviously the most glaring piece of evidence supporting that argument. So too is a .298 xwOBA that’s light years away from his .376 wOBA. Perhaps the most concerning metric is Diaz’s sudden uptick in grounders. The 32-year-old’s ground ball rate – 54.4% – is currently over 50% for the first time since the 2017 season. Of course, it’s still early, but more ground balls generally aren’t a good thing for hitters where fantasy production is concerned. You obviously want fewer of those.

It’s also worth noting that in 2017, along with a 53% ground ball rate, Diaz hit just .223 with a .265 on-base percentage. Of course, we’re talking about two different sets of data from two different seasons, but the catcher’s walk and strikeout rates from that season are eerily similar to his early-season numbers so far.

• Elias Diaz In 2017: 200 PA, 53% ground-ball rate, 5.5 BB%, 19.0 K%, .273 BABIP, .308 xwOBAcon
• Elias Diaz in 2023: 79 PA, 54.4% ground ball rate, 7.6 BB%, 19.0 K%, .400 BABIP, .348 xwOBAcon

There’s also the fact that Diaz isn’t nearly as productive on the road as he is at home. The catcher is hitting .273 with a .347 on-base percentage, a .688 OPS, and a 94 wRC+ away from home compared to a noticeably different .429 average, a .467 on-base percentage, 1.181 OPS, and a 192 wRC+ at Coors Field.

Now’s the time to trade Diaz before his production drops off, particularly if there’s a catcher-needy manager in your league.

Andres Gimenez, Cleveland Guardians

We’ve been here before with Andres Gimenez. Thanks in part to the ability to make a solid amount of contact, or rather not to swing and miss all that much with a 20.1% strikeout rate and a 26.2% whiff rate, Gimenez hit .297 with a .371 on-base percentage in 557 plate appearances last season despite a .326 xwOBA and a .368 xwOBAcon.

Of course, there were other metrics involved. A .353 BABIP certainly had something to do with the high average, especially when combined with just a 37.8% hard-hit rate. While Gimenez’s barrel rate finished at only 6.2%, which was in the 33^rd percentile league-wide, he was able to reach 20 home runs thanks to a regular role in Cleveland that netted him 558 plate appearances.

The infielder still has a regular role in Cleveland, but he’s hitting just .238 with a .319 on-base percentage in 95 plate appearances this season, adding a home run and six stolen bases. That doesn’t necessarily scream “overvalued,” but there isn’t much here to suggest a rebound is coming, statistically speaking.

Because while the stolen bases are a positive, Gimenez’s xwOBA has dropped to .299 with his xwOBAcon falling to a .325 metric. Elsewhere, he’s managed just a 23.9% hard-hit rate so far and has collected only one barrel in 67 batted ball events, good for a 1.5% barrel rate.

The stolen bases are certainly a positive, but if there’s anyone in your league thinking a return to form might be on the cards based on Gimenez’s 2022 metrics, now might be the time to trade the infielder. Even if it’s just on name value alone, his fantasy trade value might not go up all that much from here.

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