The Marlins? They’re out of it. At some point it seemed like they might have a chance, but now they’re out of it, ever so out of it, so they’ve gone into sell mode. The Marlins are used to being in sell mode. The Mariners? They’re not out of it. They’re out of it within their own division, but they’re close to a wild-card spot, like a lot of the American League. They’re close despite dealing with a thin and injured pitching staff. The Mariners are simultaneously too good to sell, and too bad to buy hard. Not to mention the farm isn’t good enough to buy hard anyway. The Mariners haven’t appeared to have that many options.

Put it all together, and that’s how you get a trade like this:

Mariners get

Marlins get

The Mariners could really use a starter. But also, they could really use a reliever, and Phelps remains under team control for 2018. So, he’s not just some kind of stretch-run rental. And although he’s no Kenley Jansen, he’s pretty good and awfully interesting. The price is four guys from the low minors. We shouldn’t pretend like any of us have any idea what they’re going to become. It’s another Jerry Dipoto exchange of low-level depth for high-level, shorter-term security.

From the Marlins’ side, they like what they’ve done:

The #Marlins thrilled by return for Phelps:CF Brayan Hernandez, 3 fringe pitching prospects Brandon Miller, Pablo Lopez, Lucas Schiraldi — Bob Nightengale (@BNightengale) July 20, 2017

We’ll get to that. Hernandez is the highest-rated player of the group. Let’s just ignore for the moment that of course the Marlins are thrilled by the return; otherwise they wouldn’t have agreed to the trade in the first place. Trades are only agreed to when both sides are happy. The Mariners, also, are presumably thrilled. Phelps might not be the most interesting player here in the long term, I don’t know, but he’s the most interesting player today. Let us first examine David Phelps.

While Phelps is nearly 31, he had his big breakout in 2016. What was behind the surge in performance? There’s not much of a mystery. Phelps started throwing a whole lot harder. He pitched better as a consequence. The relationship there is direct.

Where Phelps previously worked with his fastball in the low 90s, he started to hang around in the mid 90s, and everything was peaches. It’s hard to go wrong when you gain three ticks, and Phelps, for the first time, piled up the strikeouts. He spent nearly the entire season as a reliever, and although he’d relieved before with the Yankees, in 2016 he really took to the role. Phelps became a real weapon, and, more than that, he became a weapon who could work more than one inning. The Marlins had discovered something, and they kept Phelps as part of what they hoped would become a shutdown relief corps.

Phelps, this season, has performed a little worse. He hasn’t been bad. He’s been perfectly fine. He’s just been worse. With that in mind, I’d like to share a big table:

David Phelps, Last Two Years Season K-BB% FIP- GB% Strike% 1st-Strike% Zone% Contact% O-Swing% FA mph 2016 22% 70 46% 62% 56% 54% 76% 22% 94.7 2017 15% 89 47% 63% 60% 52% 78% 24% 95.0

Phelps has been worse, but by other measures, he’s been basically the same. This year, he’s actually thrown a few more strikes. He’s thrown a few more first-pitch strikes. He’s still not that easy to hit, and he hasn’t given back any of his velocity. Check out this image, comparing 2016 Phelps and 2017 Phelps by pitch velocity and spin rate. The biggest difference is just that 2017 Phelps hasn’t messed around with the odd changeup. Otherwise, he’s throwing virtually the same pitches.

The point is just that I don’t think Phelps has actually changed. His performance has changed, but I think his talent level is roughly the same. His numbers this year are probably a little too low. His numbers last year were probably a little too high. Safest, I’m guessing, to just combine 2016 and 2017. You want a bigger sample anyway, and last year is when Phelps started throwing the pitches he has right now.

Since the start of last season, Phelps owns a 67 ERA-, a 77 FIP-, and an 82 xFIP-. Although that’s short of elite, it makes Phelps out to be similar to, say, Ken Giles, Brad Hand, and Cody Allen. He should be able to provide crucial outs within the Mariners bullpen, which has sorely needed depth behind Edwin Diaz and Nick Vincent. Even Diaz himself has sometimes been shaky, and so Phelps has a role to fill. And although he’s a righty reliever, he can hold his own against lefty bats, thanks to his cutter and curveball. That’s another bonus, since the Mariners’ lefty relief has been inconsistent.

Mostly, that captures David Phelps. He started throwing hard last year, turning himself into a quality setup arm. He should be pretty good down the stretch, and next season. But there’s just one more twist. Phelps, in the majors, has both started and relieved. Last August, the Marlins actually let him start five times. He threw just 24.1 innings, and he topped out at 96 pitches. He struck out a third of his opponents, running a 74 FIP-. In other words, he didn’t pitch worse. And his stuff held up. As a reliever, Phelps’ fastball averaged 94.9 miles per hour. As a starter, it averaged 94.3. Across the board, he was down just about a half of one tick. It was enough to make you wonder what might be possible.

Phelps hasn’t started this season. He’s topped out at 42 pitches. He probably isn’t going to make an immediate shift into the Mariners’ rotation. But there’s some chance he could attempt that shift next spring. The Mariners, at once, might’ve traded for short-term bullpen help, and slightly longer-term rotation help. I don’t want to make too much of the possibility, but Dipoto mentioned Phelps’ versatility in the official trade announcement. It’s something to think about, months from now.

At last, there’s the matter of the return. Phelps wasn’t free. It feels like he came effectively free, but that’s only because we’re so bad at balancing the longer term against the short. Hernandez, Miller, Schiraldi, Lopez — they haven’t yet gone up against advanced competition. They’ve all been plucked from the low minors, and the highest-rated prospect among them is Hernandez, a 19-year-old center fielder with four times as many strikeouts as walks in low-A. He’s a project. Everyone there is a project. When Eric evaluated the Mariners’ farm in April, Hernandez was given a Future Value rating of 40. He probably isn’t going to hit enough.

Then you have the so-called fringe pitchers. Each has something different you could like. Schiraldi’s a reliever with big strikeouts and a control problem. Lopez is a starter and a strike-thrower who might not miss enough bats. Miller is a low-ceiling starter who’s solid across the board. The kind of guy who might just avoid prospect lists entirely on the way to becoming a competent No. 4. Not that that’s a lock. Not that that’s ever a lock. But the Marlins didn’t come away here empty-handed. They’re just probably going to be waiting for a while.

But that’s what these trades are about. The Mariners dealt some players they might not miss for a while. Perhaps none of them will ever make it. The Marlins see it as a package of four guys they can dream on. And the major-league piece is a greatly-improved reliever who might, just might, also be a greatly-improved starter, given the chance. Phelps isn’t the best player getting traded around this deadline. He is, though, one of the more interesting ones.