There is a reason it's unwise to make sweeping determinations about players during the first month of the Major League baseball season. In the small sample of about 30 games, a hot or cold streak can often be mistaken for a player either breaking out or dropping off.

When a player gets hot in the middle of a normal season, it's easy to see it for what it is. But in April, when there is no other information to go on, it sometimes leads to grand generalizations that a guy has taken a big step forward in their development or that they're suddenly some brand new player.

New York Yankees shortstop Didi Gregorius got off to a ridiculous start this season as he looked like an MVP candidate through the first month of 2018. However, the 28-year-old has come upon some hard times over the last few weeks. For fantasy owners, the question is whether this is just a slump -- something all players go through -- or whether regression has hit him square in the face.

In weeding through the numbers, is Gregorius a good buy-low candidate? Or is he simply an above-average player that played over his head during the first month of the season -- one that owners should be looking to maximize value for?

Let's explore.

Hot-Start Didi

Through 40 games this year (175 plate appearances), Gregorius is batting .255/.343/.537 with 10 home runs, 31 RBIs and 30 runs scored. He's drawing walks at a rate (12.0%) he never has before (5.9% career walk rate), and he's cut down on his strikeouts, from a 14.4% career rate to 12.6% in 2018.

Gregorius' .282 isolated power (ISO) is a career high by a wide margin (his previous high was .171 in 2016) and after a 4.1 fWAR season last year, he's already at 1.5 this year. He was April's American League Player of the Month, for crying out loud!

Unfortunately, his numbers have taken a steep hit over the last couple weeks.

Slumping Didi

After a three-hit game against the Minnesota Twins on April 25, Gregorius' batting average reached a season-high .372. Since then, he has seen it drop 117 points -- to .255 -- by hitting just .127 in his last 75 plate appearances.

Didi's numbers have done a complete 180 across the board. His strikeout and walk numbers have flipped, and he's stopped hitting almost entirely.

At least he has a sense of humor about the whole thing.

Is A Rebound Coming?

There are reasons to believe Gregorius will turn things around, even if he doesn't start hitting the way he did in the first few weeks of the season.

First and foremost, his batted-ball data is pretty close to what it was prior to his slump. His hard-hit rate through April 25 was 38.4%, and since then it's 36.2%. And his current soft-hit rate of 22.4% is only slightly higher than what it was (19.2%) during his hot streak.

One big difference has been where Gregorius has been hitting the ball. During his early-season hot streak, he was pulling the ball a lot more -- 49.3% of the time compared to 34.5% during this cold stretch. That's a big deal for a left-handed hitter who plays with that short porch in right field at Yankee Stadium.

And it's clear that pitchers are stay away from him more frequently.

Gregorius is actually seeing more fastballs during his slump (57.6%) than he was when he was killing the ball (56.1%), so the big difference is pitch location. The split heat maps above show pitchers are working hard to stay away from the power zone he took advantage of early on in the season.

What does that mean for fantasy owners?

Buy! Buy! Buy!

Gregorius' ridiculously hot start was unlikely to sustain itself for the entire season. Ever since 2016, he's been a good and improving player, with a wOBA of .319 in 2016 and .335 last season. Like many players, he's increased his power numbers dramatically over the last few years, going from 9 homers in 2015 to 20 in '16 and 25 a year ago.

His early-season success (.514 wOBA) was clearly unsustainable. Yes, some regression has hit, but that doesn't mean he has lost his value as a high-impact fantasy asset.

One should expect Gregorius to pull out of this slump and figure out a way to adjust to what pitchers are doing to him. He has been successful with a lower pull-rate the last two seasons, and it's likely that, by the end of the season, he'll finish with a slash line that looks comparable to last year's .287/.318/.478. In fact, our models project him to hit .291 with 23 homers and 73 RBI over the rest of the season.

Now is the perfect time to go fishing for Didi, using his recent slump as a catalyst to buy low on a player that has been one of the steadiest fantasy assets over the last few seasons.