The Rays shocked much of the baseball world by designating first baseman C.J. Cron on Tuesday, despite Cron being one of their best hitters and having the best season of his career in 2018.
If you're Cron, you've gotta wonder what, exactly, you're supposed to do. You club 30 homers, you slug .493, you raise your OBP nearly 20 points … and you get let go? Baseball … it's a tough racket.
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But it is becoming increasingly clear that the position Cron plays -- first base -- is going through a dramatic transformation in the consciousness of MLB teams. First base used to be the position where you put your biggest bat, a position you locked down with a power hitter, gave a big contract to them and then forgot about it for the next half-decade. But today's teams just don't value first the way they used to. And Cron's not the only example.
As a bit of thought experiment, in the wake of Cron's surprising departure from Tampa Bay, I thought today we'd look at the Top 20 first basemen in 2018 by OPS+, along with where they are in their careers, how they are valued by their teams and the market. What's most interesting about this is that the days of Don Mattingly, Todd Helton and Jeff Bagwell -- one guy manning first base for a team for a decade -- are mostly behind us. The position is more transitory than ever. It is, like many other positions, for-hire.
• Free agents, by position
• Free agents, by team
The parameters for this list, by the way: at least 300 plate appearances in 2018, with at least 20 percent of their games played at first base. Twenty percent might seem a little low, but that's sort of the point: It's a position you can increasingly just switch in and out.
20. Yuli Gurriel, Astros, 108 OPS+
Gurriel took a step back in 2018, and even though he's under team control through '23 and not arbitration eligible until '21, Houston is reportedly already looking into possible replacements at first base. In fact, general manager Jeff Luhnow now says he sees Gurriel in more of a "utility role."

19. Brandon Belt, Giants, 108 OPS+
Giants fans have been after Belt for seemingly his entire career, which is why his regression in 2018 (his worst OPS+ since his rookie year) has fans eager to see him shipped out of town. He's signed through '21, a deal the Giants would love to have off their books now and, frankly, a perfect example of the phenomenon we're talking about. Signing a slightly-above-average first baseman to a six-year, $79 million dollar deal is much more of a '16 move than a '19 one.
18. Justin Bour, free agent, 110 OPS+
Traded to the Phillies as part of their ultimately fruitless non-waiver Trade Deadline push, Bour didn't do much in Philly, hitting only one homer in 29 games. The Phillies designated him for assignment just last week, which marks the first of the 20 best first basemen in baseball just to be dumped unceremoniously on the waiver wire this month. There will be more.
17. Josh Bell, Pirates, 111 OPS+
Bell certainly looks like a power hitter, but he sure wasn't one in 2018, hitting only 12 homers after bashing 26 the year before. His OBP went up, but the Pirates need, more than anything else, some pop in their lineup. He's locked into the first-base spot next season, but that'll end if he only hits 12 homers again. Right now, his primary advantage is how cheap he is heading into this third full season.

16. Derek Dietrich, free agent, 112 OPS+
And here's your second waiver-wire bait. Dietrich played more of the outfield last year than at first base, but he still counts here, and his release by the Marlins inspired far fewer headlines than Cron's. But yeah; here's another Top-20 first baseman you can have without giving up trade assets.
15. Ryan Zimmerman, Nationals, 114 OPS+
Zimmerman has been around so long that he's an original National, but his contract expires this offseason. The Nats have an $18 million option they'll likely try to renegotiate. The club probably wants to keep him around so he can retire a National, and he can still rake when healthy. But if he were in, say, his third year as a National rather than his 15th, his return would be far less of a certainty.

14. Matt Olson, A's, 116 OPS+
Olson played every game for the A's last year -- a team that was one of baseball's happiest surprises. However, it should be noted that his offense was way down from what the A's might have been hoping for after his 2017 campaign. He hit only five more homers in 2018 (from 24 to 29) despite 444 more plate appearances. Still, he's a Gold Glove Award winner and a linchpin of everything the A's are trying to do. But he might need to tick up that HR/AB ratio if he wants to start talking about an extension anytime soon.
13. Jose Abreu, White Sox, 118 OPS+
He had the weakest season of his career with the bat, and he has lost much of his once-formidable trade value. Abreu will be a free agent after this season, so he'll likely be dealt at some point, but he'll be 32 when he hits the market, at a lower point in his career than, say, the just-released Cron. And Abreu might have to become a full-time DH at some point anyway, so he's likely to find his market chillier than he wants next winter.
12. Cody Bellinger, Dodgers, 120 OPS+
This is the sort of superstar first baseman you're supposed to be seeing minted every year, right? He won the NL Rookie of the Year Award in 2017, he played every game in '18 (impressive for a team that is constantly shifting its lineup and rotation around), and he won the NL Championship Series MVP Award. Bellinger is still not entirely reliable against left-handers, and he spends half of his time in the outfield anyway. (So much time, in fact, that there are two other Dodgers ahead of him on this list.) Bellinger is the traditional young first base star we're used to seeing. But he's only a first baseman here as a technicality.

11. Anthony Rizzo, Cubs, 121 OPS+
Despite what your fantasy baseball formats might tell you, he is not, in fact, a second baseman. Rizzo is still the solid beating heart of this Cubs team, which is still pretty fantastic despite all the ugliness that went down late in the year. The Cubs have team options on him at $16.5 million for 2020 and '21, and they'll surely pick them both up. The first-base market hasn't dried up that badly.
10. Justin Smoak, Blue Jays, 123 OPS+
The ultimate post-hype sleeper, Smoak has put together two excellent seasons in a row in Toronto. It hasn't much helped the team either year, though, and Toronto is reportedly considering trading Smoak after picking up his option last week. He'll be a free agent next season, though, and he's striking out more and more every season. He'll be about to turn 33 when he hits the market in a year. Would anyone give him more than two seasons? If that?
9. C.J. Cron, free agent. 123 OPS+
We have covered Mr. Cron. Note that he's three years younger than Smoak, and two years younger than No. 8 on this list.
8. Jose Martinez, Cardinals, 124 OPS+
We come to another person on this list whose team is desperately trying to trade him. To be fair, the Cardinals are trying to trade Martinez because he's far-below-average defensively as a first baseman; if he were even average at the position, they'd be happy to have him man it for the next few years. He'll be a DH somewhere in a couple of months.

7. Joey Votto, Reds, 125 OPS+
Will any first baseman ever get a contract like Votto's ever again? He has certainly earned most of the 10-year, $225 million extension he signed in 2012 -- though there are quite a few years to go. But it's difficult to imagine in this day and age -- with teams wanting flexibility, particularly at first base -- anyone giving that kind of massive contract to someone who can only play first base. Votto signed that deal just six years ago, and it feels like it was a lifetime ago.
6. David Freese, Dodgers,126 OPS+
So here's a surprising name to see on this list. Freese quietly had the second-best year of his career in 2018, enough for L.A. to bring him back for '19. You may see him platooning with Bellinger, as well as the other Dodger on this list, plenty in '19. But look how little the they got Freese for: $4.5 million, one year. If you can find the sixth-best-hitting first baseman for that little, why spend too much for anybody?
5. Jesus Aguilar, Brewers, 135 OPS+
Aguilar had an incredible season in 2018, but he did it after years of being a journeyman and sort of proving the overarching point that you can find these guys anywhere if you look hard enough. (The Brewers had just done it with Eric Thames the year before, after all.) Aguilar is not arbitration-eligible until after he's 30 years old, which is the best endorsement for his services that there is.
4. Paul Goldschmidt, D-backs, 139 OPS+
Now, we're into the superstar levels, and Goldschmidt's numbers would have been even higher if he hadn't have gotten off to such a slow start. He's now reportedly on the trade market, and he should fetch a healthy price, even with just one year left on his deal. But Goldschmidt will be 31 next year. How many years do you think any team would sign him for? Three, four tops? What he brings back from any team that trades for him will tell us plenty about the state of first-base-exclusive players moving forward.

3. Freddie Freeman, Braves. 140 OPS+
An NL MVP Award candidate until he faded late, Freeman is the closest thing we have to a franchise linchpin at first base -- the guy you build the rest of the roster around. He's signed for three more years -- just enough time for the rest of the superstars to mature around him. Put together three more years like he just did, he'll be pretty much in the same spot as Goldschmidt come 2021.
2. Matt Carpenter, Cardinals, 143 OPS+
Carpenter was a monster from May to August 2018, bookended by some tough months. He's a better third baseman than he's given credit for, and that might be where he moves if the Cardinals trade for Goldschmidt. Or maybe they'll sign Josh Donaldson and move Carpenter back to first. Either way, Carpenter is hardly exclusive at any position. He turns 33 on Monday.
1. Player Page for Max Muncy, Dodgers, 161 OPS+
And here's the best argument that you can find a stud first baseman anywhere. After years of floating around, Muncy showed up and just mashed in 2018. Muncy, Bellinger and Freese will alternate at first base in 2019 -- and likely do much better than almost any one first-base-exclusive player could.
Poor C.J. Cron. Against this, he never stood a chance.