On Wednesday's episode of the Fantasy Baseball Today podcast, host Adam Aizer asked us a simple question: Are we buying it?

We went through a list of some of the season's biggest surprises to see which hot starts we are and aren't buying. Here's an in depth look at some of those players, along with a handful of others, with five hot starts I'm buying, and five more I don't believe in. 

Lucas Giolito
BOS • SP • #54
ERA2.85
WHIP.98
IP60.0
BB20
K69
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Buying it

I was already starting to buy it in mid-April, and I'll remember his April 17 start vs. the Royals as the turning point. He made it through just 2.2 innings due to a hamstring issue, but that was the best he'd ever looked in the majors -- he struck out five and picked up nine swinging strikes on just 36 pitches. And he hasn't slowed down since, striking out 46 batters in 41.1 innings with a 1.74 ERA in six starts since coming off the IL. He's added nearly 2 mph to his fastball while increasing the spin — and as a result, the perceived rise on the pitch — but has actually kept his changeup at the same speed, while adding 2 inches of drop, per BrooksBaseball.net. That has been a devastating combination for Giolito, and his slider has been even better; allowing just two hits on the pitch, while inducing a whiff on more than half of swings against it.

This is, truly, the Ace Who Was Promised.

Derek Dietrich
NYY • 2B • #12
BA0.254
R24
HR17
RBI35
SB1
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Not buying it

In this instance, it's not so much the skill set I'm not buying, because Dietrich has always been a good hitter outside of Marlins Park, sporting a career .270/.352/.493 line. In fact, his per-600 plate appearance pace would land him squarely in the realm of Fantasy relevance: .270, 83 R, 27 HR, 73 RBI, 2 SB.

The problem? I don't trust the Reds to play him even close to every day. He has just 11 plate appearances against lefties this season, and playing time is going to be even more difficult to come by when Scooter Gennett returns from the IL. That's a bummer, because Dietrich's .669 career OPS against lefties suggests he could be passable enough as an everyday option. I just don't think he'll get the chance.

Brandon Woodruff
MIL • SP • #53
ERA3.22
WHIP1.09
IP64.1
BB17
K75
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Buying it

Usually, pitchers bring the heat to get ahead in counts, and then start to mix in more breaking stuff to try to put batters away. It makes sense; pitches that bend and dart are going to be harder to make contact with. Even pitchers with great fastballs work this way — Jacob deGrom drops his fastball usage to 53% with two strikes, from 64% on the first pitch of the at-bat.

Most pitchers don't have Brandon Woodruff's fastball, nor his confidence in it. When Woodruff gets two strikes, he ups his four-seamer usage from 52% on the first pitch and 45% overall to a whopping 57% with two strikes. If Woodruff gets ahead, he's going to challenge you up. And chances are, he's going to strike you out — 41.2% of plate appearances ending with his four-seamer have been strikeouts. You can't fake stuff, and Woodruff's got that in spades, ranking 10th in Aaron Sauceda's ACES metric this season.

Josh Bell
MIA • 1B • #9
BA0.338
R39
HR17
RBI48
SB0
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Buying it

Bell worked to improve his swing prior to 2018, looking to generate more lift and put his natural power to better use. That didn't quite pay off, but we saw signs of it in the second half. Even still, what he's done so far is astounding, as he has turned himself into one of the premier power sources in the game. He's already at 17 homers, while sporting a .338/.405/.706 line, with the batted ball metrics to back it up. He is in the top 4% in the league in barrel rate and top 1% in average exit velocity and hard-hit rate, per baseballsavant.com. I wouldn't expect Bell to sustain all of that, but two months of this is pretty hard to fake. He's a top eight first baseman moving forward.

Tommy La Stella
SEA • 2B • #4
BA0.302
R28
HR12
RBI33
SB0
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Not buying it

What makes buying it easier with Bell is the prospect pedigree and existing track record that suggested at least something like this was possible. For La Stella, there is essentially no precedent for this whatsoever. His 12 homers are already a career high at any level; in fact, this is the first time he's hit more than six homers at any level since his A-ball debut in 2011 as a 22-year-old. I can buy a helpful batting average for La Stella thanks to his excellent plate discipline, but you're still looking at an Andrelton Simmons-esque bat, with no speed. That's not a useless player, but it's not a must-own one, either.

Austin Meadows
DET • DH • #17
BA0.356
R21
HR12
RBI31
SB6
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Buying it

Prospect heads never really lost faith in Meadows, even as he struggled to make much of an impact once he got to Triple-A. In 178 games in Triple-A he hit .264/.322/.446, with 22 homers and 31 steals. That's not a nothing skill set, but it didn't exactly scream "impact Fantasy player". So, chalk this one up as a win for the scouts. He has maintained an average strikeout rate while pushing his walk rate up to 9.2% so far this season, and taking a big step forward as a power hitter. His launch angle is up, as is his average exit velocity, and Baseball Savant's expected stats show a legitimate star: .322 average, .566 slugging percentage, both within the top 10% of the league. Even with some regression, Meadows has clearly taken a step forward, and looks like a legitimate 25-30 homer, 20-steal guy.

Alex Gordon
KC • LF • #4
BA0.277
R32
HR9
RBI37
SB3
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Not buying it

As with La Stella, I'm not exactly rejecting the possibility that Gordon can be a useful Fantasy option thanks to his strong plate discipline. But we've already seen a drop-off in his performance of late, with a .772 OPS in the month of May. I would expect a useful batting average from Gordon, and perhaps a decent amount of runs, but the power gains probably won't hold.

Hunter Pence
SF • DH • #8
BA0.308
R29
HR11
RBI37
SB2
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Not buying it

This is an incredible story, for sure; Pence looked like he was on his way out of the league after hitting .226/.258/.332 as a 35-year-old with the Giants. He got a relatively late offer to join the Rangers in spring training and has done nothing but rake. It's been excellent to watch, but I'm skeptical it will last. Pence is unlikely to hold up to an every day role, and he'll need to hit this well to be Fantasy relevant as a part-time player. That alone is enough garner skepticism.

Steven Matz
STL • SP • #32
ERA3.55
WHIP1.34
IP50.2
BB16
K51
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Buying it

Matz is several tiers below Woodruff or even Giolito, but he deserves more credit than he's received going back to the end of last season. Sure, his 4.68 FIP in 2019 suggests worse days ahead, but a 4.11 xFIP and 4.13 SIERA show reasons for at least some optimism; his 3.77 DRA points to even better. Over his past 17 starts, Matz has a 3.00 ERA and 3.85 xFIP with 97 strikeouts in 90 innings. Is he an ace? Of course not. But that's a useful Fantasy option, someone who probably needs to be universally owned at this point.

Zach Davies
WAS • SP
ERA2.19
WHIP1.23
IP61.2
BB19
K42
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Not buying it

Through three months in 2017, Jason Vargas sported a 2.22 ERA; In 10 starts in 2018, Reynaldo Lopez had a 2.93 ERA; Matt Harvey had a 3.64 ERA through his first 12 starts with the Reds last season.

The point is, these things happen sometimes. That's not to take everything away from what Davies has accomplished so far, except to say that … it's not sustainable. You can get away with this kind of trick for a stretch, but unless you have a truly standout skill — elite control, tons of groundballs, a preternatural ability to induce infield fly balls at a high rate — it's hard to succeed without any kind of swing and miss ability. Davies doesn't have any of that, and he pitches in a tough home park. The wheels are going to come off sooner than later, as an xFIP over 4.50 hints.