Dynasty Baseball Buy or Sell 3-15-21

by Jason Beckner
Dynasty Baseball Buy or Sell 3-15-21

Welcome to the 3-15-21 edition of Dynasty Baseball Buy or Sell

St. Patrick’s Day is in two days (March 17th) and as someone that has Irish heritage and lives in greater Chicagoland ("Chi-rish" Chicago-Irish), this is a favorite holiday of mine. The corned beef & cabbage, the Guinness beer, the folk music, the bagpipes, all of it brings me great joy.

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I thought it would be fun to share some of the more popular Irish-American baseball players.

Again these are just a few of my favorites. I highly recommend you check out the Irish American Baseball Hall of Fame (IABHOF). Similar to the Baseball Hall of Fame the IABHOF has a yearly class and includes more than just players. They also elect announcers, actors, and other people that have a great influence on baseball.

Now let’s take a look at some players that are worth buying and selling in dynasty leagues.

Be sure to check out Dave Eddy's 900+ deep Dynasty Rankings.  In addition check out John's 2021 top 150 Prospect Rankings.

Dynasty Baseball Buy or Sell 3-15-21

Check out last weeks Buy or Sell article.


Tyler O'Neil, OF, St. Louis Cardinals

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Tyler is a young (25yo) power-hitting outfielder for St. Louis. He hits from the right side of the plate and tends to be a bit pull-heavy.

After being drafted by Seattle in the third round of the 2013 MLB Amateur Draft, he was traded to St. Louis at the deadline in 2017. Which has been a good change of scenery for him, as the Seattle outfield is crowded with young up-and-coming prospects.

His minor league numbers are great, with the power and speed really standing out. From 2013 to 2019 he hit 140HR and stole 55 bags in 556 games. That averages to a 40HR and 15SB for a 162gm (625PA) season.

However, his productivity has not quite translated to the big leagues. He made his debut in 2018 for St. Louis, primarily as a bench bat.

As a part-time player, he only slashed 229/291/422 & 713OPS, while on the other hand, the counting stats have been there 21HR 125/R+RBI and 6SB in 450PA across 3 seasons.

Now in 2021 I believe the true breakout is coming. He is set to get consistent playing time as the starting left fielder for St. Louis. Which should help with his plate discipline.

I noticed that Tyler’s whiff% has declined 12.2% since 2018. The chase % has also declined from 32% (2018) to 25.2% (2020), clearly, he is becoming more patient and adjusting to major league pitching.

If Tyler can stop being so pull-heavy and start driving the ball the other way. I could easily see 20/10 seasons as a full-time outfielder with the capability of 30/15 seasons. This would be a great addition to any dynasty leagues that start 3+ outfielders.


Matt Manning, RHP, Detroit Tigers

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When you think of Tigers pitching prospects you generally think of Casey Mize or even Tarik Skubal. However, the name that you should really be paying attention to is Matt Manning.

The “veteran” of the big 3 pitching prospects in Detroit, Manning was drafted 9th overall in the 2016 MLB Amateur Draft. Manning is currently ranked 25th via MLB Pipeline’s top 100 prospect list and John has him ranked 66 on his top 150 prospect list.

The fastball is the best offering of his three-pitch mix. Manning uses his tall frame (6’6) to generate a great amount of velocity. The velocity tops out at 99-100 and generally sits 95-96.

The secondary pitches are also above average. His curveball is an excellent complement to the fastball. He is able to generate a high spin rate on his curveball, and is more of the traditional 12-6 break.

In 2018 he really started to refine his changeup. While still a work in progress, the changeup could eventually end up being one of Manning’s better put-away pitches.

His minor league numbers really stand out. In 331IP across 3 levels he holds a 3.04ERA 1.12WHIP 2.60FIP and 410K (31K%). That’s good enough for a little more than 1K per IP.

Another thing that stands out, especially for a young starter are his splits. He is just as tough on lefties as he is against righties.

2019 Double AERAKWhip
vs Left2.64711.10
vs Right2.48770.87

I think Manning is primed to take a big jump in 2021, and continue to grow into a high-end SP2. He can end up giving you 150+K & 15W while also maintaining great ratios for years to come.


J.D. Martinez, DH, Boston Red Sox

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J.D. Martinez has been one of the top hitters in all of MLB for the better part of the last decade. If you have been paying attention you know the name and the accomplishments. Which include multiple all-star appearances and MVP caliber seasons. Including 4 seasons of 30+HR and 100+RBI seasons, including a league-leading 130 RBI in 2018.

Now entering his 33-year-old season, it might be time to sell. There are several advanced metrics that project the end is near to his high productive seasons.

First off the exit velocity has me concerned. The exit velocity has been steadily declining. In 2015 J,D, was in the 97th percentile in exit velo (91.3). Since 2015 there has been a steady decline year over year to a 5 year low of 89.5 in 2020.

Another metric that is declining is the barrel rate. In 2017 we saw his barrel rate climb to 19.2% (98th percentile) but has steadily declined every year since. For 2020 the barrel rate was down to 11%(73rd percentile).

In addition to that, the hard-hit rate has also seen a steady decline from 52.2% (99th percentile) in 2018 down to 41.6% (63rd percentile) in 2020.

The decline continues in yet another metric and that’s his xwOBA. While normally in the top 1% in all of MLB for xwOBA, J.D. has seen his xwOBA decline from .427 in 2017 to .418 in 2018 to .388 in 2019 and then again to .319 in2020. Which ranked in only the 41st percentile (YIKES!).

Aside from the batted ball metrics that make me want to sell, it’s also the position eligibility. In the majority of leagues J.D. only qualifies at DH. Which can really put limitations on your lineups.

So between the batted ball decline and DH only eligibility, J.D. is someone that I would be looking to sell before it’s ultimately too late.

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1 comment

Dynasty Baseball Buy or Sell 3-22-21 - Fantasy Six Pack March 22, 2021 - 12:00 pm

[…] Be sure to check out last weeks installment of Buy or Sell. […]


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