Two weeks ago, the San Francisco Giants were in the midst of a push to try and steal Zack Greinke away from the Los Angeles Dodgers. With a strong offensive core in place, upgrading the pitching staff was the obvious move for the team this winter, and pairing Greinke with Madison Bumgarner at the top of the rotation would have given the team one of the best pitching duos in baseball. However, their dreams of landing Greinke were dashed when the Arizona Diamondbacks came in and blew away the competition, offering a six year and guaranteeing $206 million in salary; neither the Dodgers nor the Giants were reportedly anywhere close to that number.

Over the last couple of weeks, their backup plan has come into focus; sign two good pitchers instead of one great one. First, it was Jeff Samardzija, and then yesterday, it was Johnny Cueto, with the team agreeing to guarantee $220 million to the pair over the next six years; significantly more than they were willing to spend on Greinke by himself, in fact. And this brings up an interesting question: since the Giants apparently had $220 million to spend on starting pitching this winter, would they have been better off just outbidding the Diamondbacks to land the ace they wanted, or is spreading the wealth around a better plan?

Let’s start where we usually start; the projections. But since we’re dealing with a two-or-one question, we don’t just want to look at the individual forecasts for Greinke, Cueto, and Samardzija, but the combined performance the Giants should have expected from Greinke and the cheap option who would have still had a rotation spot in the sign-the-ace plan; in this case, that would be Chris Heston. Heston will still likely make some starts for the Giants next year, since every team needs more than five starters to get through the season, but he’s the one getting the diminished role due to the team adding two starting pitchers, so we’ll compare Cueto and Samardzija to Greinke and Heston.

Here’s how Steamer projects the two pairs of pitchers for 2016, with the caveat that Steamer’s current projection for Heston includes mostly bullpen work, so his projection was manually altered to reflect his expected production as a full-time starter, putting him at about a +1 WAR level.

The Giants Options Pitchers IP H ER BB K WAR Johnny Shark 402 374 148 96 345 5.9 Chrack Greston 389 365 146 105 336 5.5

In the short-term, the numbers are pretty similar, with Samardzija and Cueto expected to throw more innings, since Heston isn’t necessarily a guy you can count on to pitch deep into games. In both scenarios, one of the two pitchers has a recent history of beating his peripherals, while the other has a history of underperforming them — though in a much smaller sample in Heston’s case — so the expected variance from their overall FIP-based WAR shouldn’t be dramatic, though you might give a slightly larger edge to the Johnny Shark combination since Cueto’s positive ERA-FIP divergence has been larger than Samardzija’s negative gap. If you’re convinced Cueto can continue to beat his FIP by a significant degree going forward, maybe Johnny Shark is more like a +6.5 WAR tandem for 2016.

But as I noted right before Greinke chose to pitch in Arizona, his value goes beyond what he does when he throws the ball off the mound. Greinke has become an excellent defensive pitcher, and he’s also been the best hitting pitcher in baseball over the last three years. Cueto and Samardzija, on the other hand… well, just take a look for yourself.

Pitchers As Hitters Pitchers PA BA OBP SLG wOBA wRC+ Chrack Greston 277 0.237 0.277 0.330 0.269 72 Johnny Shark 260 0.144 0.157 0.179 0.150 -17

Obviously, the Greinke/Heston numbers are skewed towards Greinke’s at-bats, and splitting those at-bats closer to 50/50 would drag down their combined numbers a good amount. But it’s pretty clear that the Greinke/Heston combination would have made up a decent amount of the gap in pitching value with their offense, as Samardzija and Cueto are basically replacement level hitting-pitchers. Factoring in the offensive value gained by adding Greinke’s bat, I think we can wipe out most, if not all, of the previous advantage given to the Johnny Shark duo. Of course, Heston will still pitch some innings even with Cueto and Samardzija around, and those innings would have to go to some less effective depth piece in the Greinke scenario, so there is still an argument for the team to be slightly ahead in the short-term by adding two good pitchers instead of one great one.

But this wasn’t a one year decision. The Giants walked away from Greinke because of the sixth guaranteed year, so it seems like they preferred to avoid paying a significant salary to a pitcher in his late-30s. They did guarantee the sixth year to Cueto, but he’s two years younger, so it’s a slightly different calculation. So for an apples to apples comparison, we need to look at the long-term expected performances for both sets of pitchers.

And this is where the Greinke path might have a real advantage. Jeff Zimmermann’s work with aging curves suggests that Greinke, Cueto, and Samardzija are all in the part of their careers where they should be expected to lose about half a win per season of value, while Heston is young enough to still have a flat aging curve for another few years. So, the Greinke/Heston combination would only be expected to decline by about half a win per season for the next few years, while Cueto/Samardzija would lose a win per year. In table-form, the overall future projections would look something like this.

Long-Term Projections Years Johnny Shark Chrack Greston 2016 6.5 6.0 2017 5.5 5.5 2018 4.5 5.0 2019 3.5 4.0 2020 2.5 3.0 2021 0.5 2.0 Total 23.0 25.5

Longer-term, the spread-the-risk option actually performs worse, since both Cueto and Samardzija are already in their decline phases, while Heston might be able to hold onto more of his current value for a bit longer. And, of course, going with Greinke offers the flexibility to pivot away from Heston in case he performs poorly, as the team isn’t locked in to just his performances like they are with a guy on a guaranteed deal. The flexibility to mix-and-match in the second rotation spot would have given the Giants more options, but now they’re more locked in to betting on two specific pitchers.

Now, there are a million assumptions and oversimplifications in this analysis, and reasonable people could disagree with any number of them. Samardzija clearly was paid a premium for the quality of his stuff, and if the Giants believe that they can unlock a higher level of performance by putting him with Buster Posey and Dave Righetti, then there’s upside with the Johnny Shark duo that Greinke and Heston probably don’t offer. But, on the other hand, this also doesn’t factor in Cueto’s opt-out clause; the scenario where the Giants end up paying the whole $220 million likely returns less than the +23 combined WAR shown above, since Cueto probably only opts into the final four years of his deal if he gets hurt or struggles the next two years.

I don’t think it’s entirely clear that one path was definitively better for the Giants than the other, especially since Heston now gives them a quality #6 starter, and depending on the health of Jake Peavy and Matt Cain, he might not throw that many fewer innings than he would have had he entered the year as the team’s #5 starter. There are positives and negatives to both paths, and in the end, the Giants chose to diversify their assets rather than putting in a big bet on one premium player. Bets like that have paid off plenty of times in MLB, since star players aren’t that much more valuable than regular good players in baseball.

But despite getting two arms instead of one, I’m not so sure the Giants actually ended up with less risk. Cueto’s opt-out means that they’re only paying $220 million when his deal looks like a mistake, while they could have spent $210 million on Greinke — giving the other $10 million to Heston during his arb years — and reaped the entirety of the rewards if he aged well. With no opt-out for Greinke, plus the fact that he was willing to defer a significant amount of the money he received from Arizona, I think it’s possible that the Giants may have been better off just rolling the money they paid for Cueto and Samardzija into a single big contract for Greinke. Yeah, six years for a 32 year old coming off a season where his ERA was unsustainably low was a risky proposition, but Samardzija and Cueto aren’t the safest of bets either, and by giving Cueto an opt-out, they’ve limited the upside they’ll get from spreading the wealth.

In the end, the wisdom of this decision probably comes down to whether or not Samardzija’s 2014 performance represented a real level of potential that the Giants can unlock. If they can get him back to close to a +4 WAR pitcher, then this decision will work out just fine, even if Cueto struggles or opts-out after the second year. If Samardzija continues to tease more than perform, though, the Giants may end up looking back and wishing they would have just given Greinke the sixth year instead.