Matt Carpenter has long been a man without a true position for the St. Louis Cardinals. As a four-year college player turned somewhat late bloomer, he was primed to make his way into the Cardinals starting lineup at 26, but then the guy who played his position happened to be a seemingly unmovable hometown hero.

Carpenter was very good in a bench role in 2012, but the incumbent third baseman was an All-Star, so Carpenter moved to second base, a position which he had played for a grand total of eighteen professional innings, for the 2013 season, and he was great. His defense was merely average (by Ultimate Zone Rating, he graded out as three-tenths of a run above-average at second base), but his offense was playable anywhere, so at second base, he was the sport’s most valuable player at the position.

Third base opened up, so Matt Carpenter became more or less a full-time third baseman for the 2014 and 2015 seasons, starting 155 and 141 games at the position, respectively. But in 2016, injuries and ineffectiveness from Kolten Wong coupled with the rise of Jedd Gyorko as a viable third base option left Matt Carpenter wandering the infield again. This wasn’t an indictment of Carpenter (who had a slightly down season, but he was still clearly the superior hitter of this trio) so much as a credit to his versatility. Carpenter started at least 35 games at first, second, and third base.

Matt Carpenter spent 2017 primarily at first base, partially a reaction to Jedd Gyorko’s improvement (as well as a last-ditch effort to maintain Jhonny Peralta as a Major League Baseball player), partially a reaction to Matt Adams’s career stagnation at first base, and partially a reaction to Carpenter’s decline at third base. He wasn’t “Miguel Cabrera faking it at third base to fit Prince Fielder into the Detroit Tigers lineup” bad, but he certainly wasn’t a great fielder at the hot corner. But then, in 2018, Jedd Gyorko was replaced as the fashionable infielder to fit into the lineup with Jose Martinez, who was only capable (to the extent that he is capable) of playing first base on the infield, and thus Carpenter moved back to third base.

With the acquisition of Paul Goldschmidt from the Arizona Diamondbacks, it became clear that Matt Carpenter was going to be playing third base on the most full-time basis he has since at least 2015. And given the personnel involved, this is totally fine. Matt Carpenter has a good enough bat to justify playing at first base, but Paul Goldschmidt gives the Cardinals, along with Carpenter, another elite-tier bat for a lineup in which even the worst hitters are basically league-average. Particularly if Marcell Ozuna bounces back from his disappointing 2018 season (in which he was still an above-average hitter, mind you), this lineup could be downright lethal.

An infield with Goldschmidt at first and Carpenter at third is defensively worse than one with Carpenter (or Goldschmidt) at first and Jedd Gyorko at third (Gyorko will begin 2019 on the IL, but long-term too), but it isn’t so much worse so as not to justify the offensive improvement. Over the last two seasons, Carpenter’s defensive metrics have actually been above-average at third base. He hasn’t played enough innings to declare “he’s actually an above-average third baseman”, a statement which I don’t actually believe anyway, but the numbers throughout his career suggest that while Carpenter isn’t Manny Machado or Matt Chapman at third base, he isn’t a complete trainwreck either.

But Matt Carpenter, never great in the field, is getting older, and at 33, his quick defensive reflexes run the risk of falling victim to the dreaded aging curve. It is reasonable to assume that any player of Carpenter’s age is going to decline defensively, but particularly in the case of Carpenter, who has long depended on his instincts to help atone for a solidly below-average throwing arm, the concerns are even mightier.

This doesn’t mean that Carpenter won’t still be competent at third base this year–he probably will be acceptable, if firmly below-average, at the position. Even with his defensive concerns, Goldschmidt and Carpenter make for one of the NL’s most potent corner infield combinations (there are a ton of contenders for this title–Freddie Freeman and Josh Donaldson in Atlanta, Anthony Rizzo and Kris Bryant in Chicago, Joey Votto and Eugenio Suarez in Cincinnati).

For much of the off-season, this wasn’t too concerning, as with Paul Goldschmidt a pending free agent, it was only a one-year issue for the Cardinals. But with last Thursday’s announcement (and Saturday’s confirmation) that Paul Goldschmidt had signed a five-year, $130 million contract with the Cardinals which will keep the first baseman in St. Louis through 2024, Matt Carpenter’s long-term future in St. Louis became an open question.

This isn’t to say that the presence of Matt Carpenter, to whom the Cardinals are only contractually obligated through this season (the team has a $18.5 million option for 2020, though should they decline it, they would owe Carpenter $2 million), is an argument against signing Paul Goldschmidt. Cost aside, Goldschmidt is almost certainly the safer long-term option–he is two years younger, and for as good as Carpenter has been at the plate, Goldschmidt has been the superior hitter in five of the six seasons since each became a full-time starter (in 2016, Carpenter’s 136 wRC+ barely edged out Goldschmidt’s 133–and this was also the season Goldschmidt managed 32 stolen bases and was the more valuable overall offensive player).

But it is distinctly possible, and perhaps likely, that Matt Carpenter won’t be worth the cost to the Cardinals very soon. It probably won’t be this year, and barring catastrophe, the Cardinals will almost certainly pick up Carpenter’s option for 2020 (if nothing else, they could pick up the option and trade him to a team that needs a first baseman; they made a similar move with Jaime Garcia, and that’s why John Gant is a Cardinal). But beyond 2020, re-signing a lackluster, potentially unplayable defensively third baseman in Carpenter wouldn’t make much sense for the Cardinals, and if Carpenter can still hit (given that he turned himself into a legitimate power hitter and has one of the best batting eyes in the game, his bat should age very well), it makes even less sense for Carpenter to take a lesser role (and salary) with the Cardinals.

Unless.

Paul Goldschmidt has played one professional baseball game at a defensive position other than first base–a 2009 Rookie Ball game in which he played center field. He has nowhere to go on the defensive spectrum. And if Matt Carpenter is deemed incapable of playing third base, unless he jumps back into the corner outfield role in which he had cameos early in his career (which seems unlikely, as he is notoriously slow, plus his aforementioned weak throwing arm), he would have nowhere to go but first base. But that’s where the designated hitter come into play.

As it stands, of course, the Cardinals play in the National League, which does not implement the designated hitter rule. No NL team would employ a designated hitter for the sake of a handful of games in American League parks per season. But with rule changes being proposed left and right across baseball, the oft-suggested implementation of the DH in the NL is looking increasingly more likely in the near future.

I’ve long complained about the discourse of DH discussion, but one of the most annoying pro-DH arguments I’ve heard is that it is inevitable so people who don’t like the DH shouldn’t bother to complain about it. Which is ridiculous. If you hate the DH, that’s your God-given right. But I do think that it is worth examining the positives of the DH. Offense would increase. Baseball would have far fewer totally non-competitive plate appearances. Matt Carpenter could remain a Cardinal.

Could is a loaded term–it’s not as though Matt Carpenter would just magically remain a Cardinal. Perhaps Jose Martinez would become the DH-in-waiting. But the rule would enable the Cardinals to employ and regularly start both Paul Goldschmidt and Matt Carpenter at positions which would not expose them defensively. Neither would have to be pigeonholed entirely into the DH role, a la David Ortiz, but instead, the two could alternate between first base and designated hitter and allow the team to preserve its aging superstars and spare them from a full defensive workload which could wear one of them down.

Long-term, you probably shouldn’t base your DH opinions on keeping one player into his late thirties. But if you’re more moderate in your stance on the rule and really enjoy watching Matt Carpenter be Matt Carpenter, perhaps this is something to consider.