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This is it. This is what we've been waiting for. These young, former top prospects are finally putting it together, taking the flashes we've been seeing and turning them into actual production.


Well… maybe not. Not to be the Fantasy Grinch, but not every hot start for a young player means the light is suddenly clicking on. Sometimes, a hot streak is just a hot streak.

Here are four hot starts I'm not buying.

Nomar Mazara
DET • RF • 15
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Before the season, I had this to say about Nomar Mazara:

It certainly sounds like the production is catching up to the scouting reports for the former No. 5 overall prospect, who is hitting .294/.357/.545 with 10 homers through his first 38 games of the season. I've never doubted the talent, so why wouldn't I buy this?

Because he still looks too much like the same guy he's always been. 

That's not entirely true, because there have been improvements for Mazara, who has fared better against lefties and against breaking pitches so far this season, as Jay Jaffe of FanGraphs noted Thursday. Improving against lefties was one of the keys for Mazara, and he's managed an .878 OPS against same-handers, including three of his five career homers against them.

However, he hasn't fixed his groundball tendency. In fact, it's gotten worse. Mazara hits the ball consistently hard, but he too often hits it right into the dirt. Of 254 batters with at least 50 batted balls tracked by the Statcast system, Mazara ranks 228th in average launch angle, 6.0 degrees. Last year, he was 130th out of 237 batters at 11.3 degrees. Mazara isn't hitting significantly fewer infield fly balls, and his ground ball rate has also climbed from 46.5 to 52.3 percent. 

His performance in the month of May has been a testament to Mazara's talent, but like the best moments of Eric Hosmer, it will ultimately serve as a tantalizing and disappointing sign of what we're not getting consistently. There's still no denying the talent, but the approach ultimately remains as limiting as ever. The sky is the limit for Mazara if he ever changes that approach, but for now he'll continue to frustrate. I wouldn't rank him as a top-30 outfielder, and I would be looking to move him right now. 

Javier Baez
DET • 2B •
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What's the best way to define "plate discipline?" Javier Baez has cut his strikeout rate all the way to 19.7 percent, a nearly 50 percent reduction from last season. Sure, he still never walks, but all those balls in play are adding up, with Baez off to an incredible start. By that measure, his plate discipline has undeniably improved.

However, he's still a hacker. Baez has swung at 60.8 percent of all pitches this season, including 42.7 percent of pitches outside the strike zone — the highest and third-highest marks in baseball. While it's true that you can't strike out if you never get to two strikes, it still seems like this isn't a sustainable approach. And there are some real red flags in his profile. 

To start with, while Baez does have the highest hard-hit rate of his career at 37.3 percent, he also has a 25.5 percent soft-hit rate, also the highest of his career. A total of 29.4 percent of his fly balls have gone over the fence, a huge mark. However, he also has a 20 percent infield fly ball rate. That's the definition of an "all-or-nothing" hitter, and it's hard to see how this will prove to be a sustainable approach. Baez is locked in right now, but he's still swinging at too many bad pitches and making too much bad contact to keep it up. When things go south for him, they're going to be really ugly. 

Baez still hits for enough power and swipes enough bases to be a useful option in Rotisserie. But I don't buy him as a star, and I would sell him if someone else does. 

Maikel Franco
WAS • 3B •
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Maikel Franco wasn't the same caliber of prospect as Mazara or Baez, but he was still someone we were excited about early in his career. Things didn't go as planned, but this season is exactly what we were hoping to see: a high-contact approach combined with plus power from a corner spot. 

Unfortunately, there isn't all that much evidence that Franco is truly a changed hitter. In fact, in most of the ways that we think matter for hitting, he's been the same guy as always:

2018Maikel Franco18.00%46.00%36.00%8.30%19.40%19.00%51.00%30.00%
2016Maikel Franco20.00%44.50%35.50%17.10%14.70%21.50%47.80%30.70%
2017Maikel Franco17.90%45.40%36.70%16.30%13.50%20.80%48.30%30.90%
2018Maikel Franco5.70%13.00%31.90%74.50%80.50%10.10%
2016Maikel Franco6.30%16.80%34.40%74.40%77.10%11.80%
2017Maikel Franco6.60%15.20%31.50%75.20%79.10%10.50%

Now, there are some differences, to be sure. He's making more contact than ever, and he's not hitting nearly as many infield fly balls, a possible sign that he's becoming a more consistent hitter, with fewer low points. That may be it. 

Or it may just be a bit of good luck. I want to believe this is finally the version of Franco we were promised, but I just don't think that's where the evidence points. 

Corey Dickerson
TOR • LF • 14
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There really aren't many holes to poke in Corey Dickerson's profile right now. He's cut his strikeout rate to 9.7 percent, and he's backed it up with by far the best contact rate of his career. He's hitting the ball hard and, unlike Franco or Mazara, he's hitting it in the air constantly, with just a 26.7 percent groundball rate. By all accounts, Dickerson is doing absolutely everything right.

Against righties. 

Dickerson's ability to hit right-handed pitching has never really been a question, as he sports an .868 OPS against them. That's pretty much right in line with what he's managed against them this season. However, he's basically faced no lefties so far. The Pirates have had just five games against left-handed starters, and Dickerson was only in the lineup for one of them. Of his 144 plate appearances this season, just 17 of them have come against lefties. 

To be fair, he did have a .308/.339/.481 line against southpaws a year ago, however that was largely based on a .405 BABIP, and Dickerson has largely struggled against them in his career. Either the Pirates are going to continue to shield Dickerson against lefties, in which case his counting stats will likely suffer, or he'll start seeing more of them, and his rate stats will take a hit. Either way, he won't keep this up moving forward.