Baseball has always been a game of trends. Each week in this column, we will look at players through the lens of advanced metrics and various statistical trends to discover which players are underachieving or overachieving in the hopes of identifying potential trade targets or those worth selling at peak value.
All that being said, I want to clarify what we mean by the terms “Buy Low” and “Sell High.” These terms reference an old stock strategy in which you buy an asset at a lower price point because it has lost value and sell assets when they peak in value for a larger return on your investment. However, many times when you think we are buying low, the market just keeps going lower, and you bottom out watching it crater because you thought buying falling GameStop stock was still a good idea.
Instead, a wiser strategy is to look at trends that show an asset is already on an upwards trajectory and buy before it peaks. You now have at least some evidence that there will not be any further dips in value, at least not in the short term. Then, sell assets when they go even higher.
How does that apply to fantasy baseball?
Put simply, do not buy players simply because they’ve been bad or sell them just because they’re good. In both cases, look for clues as to why. Find stats showing that a player’s value is actually on the upswing and acquire that player at a fair price, knowing his value is almost sure to keep increasing anyway. Conversely, sell players who hold widely held perceived value but for whom underlying stats show may be on the verge of seeing the floor collapse and get out now.
Thus far, we have a limited data sample, but every ball hit and thrown still tells a story.
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Buy Low
Ha-Seong Kim (SS – SD)
The Padres may have lost Fernando Tatis for an extended period of time because the baseball gods decided 2021 wasn’t painful enough for fans of the game.
Here’s the swing where Tatis was hurt tonight. It’s hard to tell exactly what is injured. Could be an aggravation of his left shoulder injury, or it could be a wrist injury. Expect x-rays tonight with a possible MRI tomorrow. https://t.co/0r7kBSlcJZ
— Inside Injuries (@InsideInjuries) April 6, 2021
Ha-Seong Kim entered the game at shortstop. He hit 133 HR and stole 134 SB in his seven-year KBO career with the Kiwoom Heroes, all before turning 25. The Padres initially signed him to a super-utility role, but he may very well end up being the team’s starting shortstop moving forward. He possesses strong plate discipline, above-average contact skills, and 20/20 upside if given enough playing time.
Yermin Mercedes (UTIL – CHW)
Yermin Mercedes is built like a pitbull and toiled nearly ten years in the minors before a team finally gave him a shot on the Opening Day roster. All he did is make history with the opportunity.
The best or nothing.
Yermín Mercedes is the first player since 1900 to begin a season with 8 consecutive hits. ???? (h/t @EliasSports) pic.twitter.com/bdkxZ8HSc6
— MLB (@MLB) April 4, 2021
“The Yerminator” is now a thing. Mercedes can hit ( .317 with 23 homers and a .968 OPS at AAA in 2019), but he’s a defensive liability as a DH-only player. Maybe he’s this year’s Jose Martinez and will flame out in short order. Then again, it shouldn’t cost much to acquire him to find out.
Julian Merryweather (RP – TOR)
Julian Merryweather surprised everyone by collecting two saves over the weekend after nearly everyone presumed Jordan Romano would inherit the role after Kirby Yates was lost for the year. However, Merryweather throws serious gas, and he has struck out five of the six hitters he has faced thus far. The fastball/changeup combo is lethal, primarily because of the velocity divide, as you can see from the overlay below.
Julian Merryweather, 97mph Fastball & 79mph Changeup, Individual Pitches + Overlay. pic.twitter.com/vPXKABfaga
— Rob Friedman (@PitchingNinja) April 1, 2021
Romano is still good in his own right, and it took Merryweather six years to make it to the majors. Merryweather could still be on waivers in your league, but if he was scooped up, you can probably get him for cheaper now before he establishes himself any further in Toronto.
Yusei Kikuchi (SP – SEA)
Kikuchi has largely been a disappointment since coming over from J. The 5.46 ERA in 2019 had nothing under the hood to inspire much hope (5.18 xFIP, 5.17 SIERA). However, 2020 saw a jump in K/9 (6.46 in 2019 to 9.00 last year), and last year’s 5.17 ERA actually had some underlying metrics to suggest an overall improvement (4.34 SIERA, 3.78 xFIP). In his first start of 2021, Kikuchi struck out 10 across six innings, and improved velocity and a new pitch are a big reason why.
After adding velocity and a new favorite pitch in 2020, Yusei Kikuchi looks like an easy breakout candidate this year. If he does, Seattle's rotation could get very interesting: https://t.co/u6m6DazPYp
— Tony Wolfe (@_TonyWolfe_) March 11, 2021
His fantasy manager is probably thrilled with the output thus far from someone drafted as a back-end starter. However, the price to acquire him may still be less than the production Kikuchi looks poised to provide this season.
Steven Matz (SP – TOR)
Steven Matz has teased frontline starter potential for years, but injuries and inconsistent results have plagued him since his debut in 2015. His first start of 2021 produced 6.1 IP of two-hit ball with 9 K’s, and the velocity has held through the spring.
Steven Matz maintained his fastball velocity (averaging 94-mph) into the sixth inning tonight.
A good process indicator to go along with strong spring results from the left-hander who's lined up to start during Blue Jays season-opening series in the Bronx: pic.twitter.com/rZKAjKLLHn
— Arden Zwelling (@ArdenZwelling) March 26, 2021
Like with Kikuchi, Matz’s manager may very well be looking to cash out now and make a profit on a player drafted late who has already paid dividends. Make an offer and see if you can buy a breakout before it happens.
Corey Knebel (RP – LAD)
Corey Knebel earned 39 saves for the Brewers in 2017, and he was well on his way to joining the elite tier of closers before needing Tommy John surgery.
Well, Knebel has regained his pre-surgery fastball velocity and changed the grip on his curve, producing a better spin rate and break. Dodgers’ manager Dave Roberts has already called on him to vulture a save after established closer Kenley Jansen secured a five-out save the night before. Knebel is a priority add in leagues that reward holds, but he’s probably next in line if Jansen starts to lose his grip on the role during his final season in Dodger blue.
Sell High
Byron Buxton (OF – MIN)
Byron Buxton has hit two HRs, stolen a base, and sits with a 1.750 OPS to open 2021 as one of MLB’s hottest hitters.
Look, I’m not saying Buxton isn’t talented, and there aren’t a bevy of metrics that show he has league-winning upside. I am saying that the 140 games he played in 2017 represent the only time the 27-year-old has ever played more than 100 games in a season. That’s a lot of incentive to cash out while you’re already ahead if you have needs elsewhere.
Chris Owings (2B/OF – COL)
Chris Owings had spurts of production for Arizona as a utility player, and only in Colorado does a veteran player like that get extended looks at the expense of younger players trying to establish themselves. Owings is hitting .400 with a double, a triple, and two stolen bases to his name after the first weekend of the season, playing far more than anyone imagined this early. If you can sell the hot start with the deference to veterans narrative in Colorado, now would be the time to flip Owings for a more sustainable asset.
Evan Longoria (3B – SF)
Evan Longoria has largely been underwhelming during his tenure with the Giants after the team acquired him in 2018. Longoria is now 35, and his torrid start to the season (three HRs, 1.250 OPS) makes him a prime sell-high candidate. No projection system has Longoria hitting more than 17 home runs or batting above .260 this year.
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Paul Ghiglieri is a featured writer at FantasyPros. For more from Paul, check out his archive and follow him @FantasyEvolves.
