In his latest trade rumblings column, Ken Rosenthal has a pretty fun story.

Here is an example of a trade that recently was discussed but never got close, and would have amounted to a bombshell if it had come to fruition. The scenario, according to major-league sources, unfolded like this: The Cubs tried to acquire left-hander Drew Pomeranz before the Padres sent him to the Red Sox for Class-A right-hander Anderson Espinoza. Simple enough. The Cubs’ plan, though, wasn’t to keep Pomeranz, who is under club control through 2018. No, the Cubs wanted to spin Pomeranz for a starter who is under even longer team control. I could not determine the identity of that starter — it was a pitcher whose “name is not out there (publicly), and probably is not going anywhere now,” one source said. In any case, the Cubs balked at the Padres’ request of infielder Javier Baez for Pomeranz, believing it too high a price. The second part of the deal — the spinning of Pomeranz for the unidentified starter — would not necessarily have worked, either.

This is an intriguing idea for all kinds of reasons. For one, what do the Cubs need with another starting pitcher? Their rotation is already pretty excellent, so making a complicated three-way trade to either acquire a #6 starter or bump Jason Hammel from the rotation while he’s running a 3.34 ERA would be a bit weird. They could use some rotation depth in case of injury, but if you’re acquiring Pomeranz — potentially the most valuable starting pitcher to be moved this month — because you want to flip him for someone even more valuable, that guy has to be pretty good, right? You’re probably not going to pay the price for Pomeranz, only to ship him off for some guy you’d stash in Triple-A, if you’re a win-now contender like the Cubs. At least, I wouldn’t think so.

Of course, it’s not entirely unheard of. The win-now Dodgers inserted themselves into the Todd Frazier trade, getting a package of prospects they liked from Chicago more than the ones they sent to Cincinnati, rather than just keeping Frazier for themselves. Maybe the Cubs knew that some other team hunting for Pomeranz was willing to part with a guy they liked for the future, and they thought this was their best chance to get a young controllable starter from a team that they don’t match up well with in trade. And perhaps they’d think about using that starter as a reliever down the stretch, strengthening a bullpen that could use an upgrade, with the idea of moving him back to the rotation next year.

So, just for the fun of it, let’s try to figure out who this mystery pitcher might be.

To find the mystery pitcher, we have to figure out which team would want to trade for Drew Pomeranz this month, has a young controllable pitcher that would be worth more than Pomeranz to the Cubs, but also wouldn’t want to just keep that young pitcher for themselves. For that series of conclusions to make any sense, it would presumably have to be a win-now contender looking to upgrade for the stretch drive, and they’d likely have to look at the young pitcher as a guy who wasn’t capable of giving them another 15 starts this season, either because he’s not good enough or because he might have an innings-limit issue. So let’s run through some candidates.

The Dodgers could potentially be a fit on the surface; this is the kind of weird move they’d be involved in, and with nearly their entire rotation sidelined with injuries, I could see them being interested in Pomeranz. And maybe the Padres wouldn’t want to trade with the Dodgers directly, given that they’re division rivals, so the Cubs thought they could insert themselves in the deal as a go-between. On that front, they check the necessary boxes.

But what young pitcher would the Dodgers offer to the Cubs that Chicago would value more than Pomeranz, that Los Angeles would also give up for Pomeranz? I think we can reasonably assume Julio Urias wasn’t the guy, as A.J. Preller would have stood on his head for a week if he had a chance to acquire Urias.

That would leave Jose De Leon as the next best option, and he does seemingly fit the bill; he’s probably roughly as valuable as Pomeranz given his current prospect status and proximity to the majors, and yet the Dodgers haven’t seen fit to call him up to the big leagues even with all their pitching injuries, as he’s battled arm problems of his own, and spent a good chunk of the first half on the minor league DL. He would make sense as a guy the Cubs could immediately promote to help pitch in middle relief for the rest of this season, and then they could work on building up his innings totals the next couple of years, potentially setting him up as a spot-starter next year and a full-time starter in 2018, when Arrieta, Lackey, and Hammel all become free agents.

And even beyond his long-term upside, it’s worth noting that the projections think De Leon could be a standout reliever in the big leagues right now. Steamer’s rest-of-season forecast projects him for a 3.20 FIP, better than every Cubs reliever not named Rondon or Strop. ZIPS liked him enough pre-season to project him for +1.5 WAR in 100 innings as a starter, projecting him as nearly a +3 WAR pitcher even before he struck out 37% of the batters he faced in Triple-A this year. This is a guy who might very well come up and go all Dellin Betances on the National League, if put in the bullpen for the rest of 2016.

Of course, that’s also why the Dodgers might not have been willing to swap De Leon for Pomeranz; after all, it’s not like they’d be getting a sure-thing health wise with the veteran lefty, so if you’re betting on talent and rolling the dice with health and workload, why not just promote De Leon yourself? And the Dodgers have been reluctant to trade younger players for older ones, even in pennant races, so the Cubs hatching a plan that required Andrew Friedman to trade a high quality prospect who appears big league ready, even in exchange for Pomeranz, might have been doomed from the start.

So, let’s see if there’s any other options out there, maybe on teams that don’t covet their young players so heavily.

The Blue Jays are known to be looking for pitching, but the only starters who fit the bill in their organization are Marcus Stroman and Aaron Sanchez, and let’s be real, Pomeranz wasn’t bringing back either of those guys.

The White Sox could sort of be a fit if they were still invested in going for it over the next few years, but the only guy they have who fits the bill is Carlos Rodon. Yeah, Pomeranz might be better than Rodon now, but how much better, realistically? Half a win over the rest of the season, maybe? A full win, if you’re really high on Pomeranz’s breakout? If the White Sox hadn’t fallen apart the last few months, maybe I could see them doing something like that, but they’re in 10th place in the AL at this point, so now would seemingly be a weird time to make a move like this.

The Mariners, with a guy like James Paxton? Ditto everything I just said about the White Sox, though it’s not hard to imagine that the Cubs would find it an intriguing idea to put Paxton and his new-found 100 mph fastball in the bullpen for the rest of the year.

The Pirates, with Jameson Taillon playing a similar role as De Leon? I guess maybe I could squint and see it, if they didn’t trust Taillon to stay healthy the rest of the year, but would the Pirates really want to give up one of their coveted young arms to marginally increase their chance of landing in the wild card game, potetnially going up against a Clayton Kershaw or Jose Fernandez as the reward? I have a tough time buying that.

The Orioles could certainly use Pomeranz, but besides Kevin Gausman, I don’t know what they could offer that the Cubs would value enough to get involved in such a deal, and I think the Orioles are smart enough to realize they would have needed to add Pomeranz to Gausman, not exchange one for the other. Dylan Bundy’s still got a little bit of trade value left, but hard to imagine the Cubs would go to this kind of trouble to acquire him at this point.

None of those options really fit, at least from my perspective. And while there are other young pitchers the Cubs could feasibly want — Josh Hader is another hard-throwing lefty who they would probably like to stick in their bullpen tomorrow — many of them are on teams that wouldn’t be logical fits as Pomeranz buyers.

So, in the end, I’m sticking with my initial guess. Based on the information Rosenthal’s source gave him, I’m going to wildly speculate that the Cubs were trying to get Jose De Leon from the Dodgers. The sad thing is we’ll probably never know, unless Rosenthal’s source wants to swing the comments and bear his soul. What do you think, anonymous tipster; want to satisfy our curiosity at the expense of your job? It would only be a slightly weirder decision than the Cubs engineering a three-way trade to land a prospect mid-season.