No matter the single-season data you use, there’s going to be a call about sample size. And it’s generally true. It’s hard to evaluate a player over the course of a season, let alone at individual points in that season. That’s why when evaluators break down a player, they typically look at a three-year sample to have enough data on hand to give a proper opinion.
We don’t have that perk in season-long fantasy baseball leagues. During the season, you have to look for the reason the player is doing what he is at that time, make a call, and decide whether or not you want to hop on board. We also have to look at what a player did a season ago when preparing for drafts because, like it or not, where a player goes is based off their previous year’s stats.
Looking at stats over the course of a season is important, but they often don’t tell the entire story. Take Nomar Mazara, for example. Mazara was off to a torrid start to 2018, hitting 15 first-half home runs—including 10 in May alone—with a home run to fly-ball ratio of 22.7. In May, that number was 58.8. Both rates were unsustainable, so luck fueled the early breakout. Mazara’s numbers ended up fixing themselves, as he hit just five home runs the rest of the season.
If you look at Mazara’s early-season numbers, you would have said he was on pace for a breakout season of 30-plus home runs as long as he didn’t get injured. The issue with that, though, is assuming he’d keep up his unsustainable performance.
It’s important to take each player by a case-by-case basis and examine the individual parts of the season and the why, instead of the season as a whole and the what.
Similar to how Mazara stood out in the first half of the season, here are some players that elevated their status in the second half. Let’s take a look at what they did, and what it means for their 2019 production.
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Adalberto Mondesi (2B/SS – KC)
Mondesi was pretty much an afterthought for fantasy owners until the second half. He didn’t really see regular playing time until late June, but he took off like a man possessed with a literal sprint to the finish line. Mondesi brought what so few players do to the table: stolen bases.
Mondesi had 32 steals on the season, with 27 of them coming after the All-Star break. Following his stellar late performance, he’s become the most polarizing player heading into 2019 drafts. I hate to bring the negativity here, but he is going to disappoint owners in a similar fashion to Jonathan Villar in 2017.
Mondesi has blazing speed, but expecting 40 or more steals is chasing last year’s success. There are a few issues with Mondesi and taking him as high as the third or fourth round. First, as Tristan Cockcroft pointed out, Mondesi attempted a steal nearly 50 percent of the time that he was on base. That attempt rate is unsustainable for any player.
The second issue is in order for Mondesi to steal, he has to get on base. Science, right? But here’s the thing with Mondesi that works against him. Out of players with at least 250 at-bats last year, Mondesi had the ninth-lowest walk total at 3.8 percent. Of those nine players, he also had the highest strikeout rate (26.5%). If Mondesi has shown that he can’t take a walk and will swing at just about anything—he swung at 54.8 percent of pitches he saw, including 79.3 percent of pitches in the strike zone and 37.1 percent out of the zone—why not pitch the corners to him? He’s not going to take a walk, so force him to get on base with his bat.
Steals are at a premium, and Mondesi (along with half of the Royals roster) can help in that category. The third or fourth round is way too rich, though. If he’s there in the seventh or eighth, I’ll take him, but I have a feeling he won’t make it there in any leagues I’m in. It only takes one person in every draft to like the guy and buy into what he did in a small sample.
Jonathan Villar (2B/SS – BAL)
Remember Villar? We just talked about him one section up. After a breakout 2016, he was going high in drafts but failed to repeat that success in 2017. Near the trade deadline, the Brewers traded him to the Orioles, who had absolutely nothing to play for.
With the throw-something-at-the-wall-and-hope-it-sticks mentality that the Orioles had last season, Villar was the someone they threw at the wall. He stuck.
Villar closed out his season by stealing 13 bases in 27 games, again making him a sought-after player. But is it real life, or is it just fantasy again?
Two years ago, Villar was getting the 2019 Mondesi treatment. After burning owners once, it seems they have a more cautious approach this time around. There are a lot of warts in Villar’s game, too, but he walked more than double the amount that Mondesi does (8.0%) and has 15-homer potential, too.
The Orioles are a mess, and they once again have nothing at stake. Villar should again get the green light whenever he wants. Of the two, give me Villar over Mondesi, if not for the simple reason that you can wait to take him rounds later. Mondesi is currently going 43rd in NFBC drafts, and Villar is going 88th.
Luis Castillo (SP – CIN)
Castillo had a lot of hype surrounding him heading into last year’s drafts based off of his good second-half performance in 2017. Unfortunately for those who reached and took him early, he was unable to turn a profit on the selection.
Castillo had a poor first half with a 5.49 ERA and a 4.77 FIP. He did, however, turn it around in a major way, limiting his walks (1.90 BB/9), upping his strikeouts (9.36 K/9), and lowering his ERA and FIP to 2.44 and 3.61, respectively, in the second half.
While long-term questions still linger about how Castillo will hold up as a starter, he seems to be on a similar path as Luis Severino after his sophomore season. Now’s the time to buy if you still can, as Castillo should carry his second-half success into 2019.
Tyler Glasnow (SP – TB)
Maybe all Glasnow needed was a change of scenery. After getting traded to Tampa Bay from Pittsburgh, he showed signs of the top pitching prospect he once was for the longest time in Pittsburgh’s farm system.
The knock on Glasnow was never the stuff, but his lack of command and control, as well as the 6’8″ starter’s ability to repeat his delivery consistently.
Whether it’s the Pirates not knowing how to maximize their pitchers’ potential (they don’t) or the Rays knowing how to maximize theirs (they do), Glasnow was able to lower his ERA to 3.94 in the second half—which aligned closer to his 3.51 first-half FIP, for what it’s worth—and improve his walk rate from 5.19 to 3.49 while not taking a huge strikeout hit.
If Glasnow can replicate this success in 2019, the Chris Archer trade could look very bad for the Pirates in the not-so-distant future. Glasnow is the 61st pitcher off the board in NFBC drafts right now, which could return a huge profit by the end of the year.
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Michael Waterloo is a featured writer at FantasyPros. For more from Michael, check out his archive and follow him @MichaelWaterloo.
