There shouldn't be much doubt that the Reds have the talent to hang at the top of the division all summer. They've put the Cardinals (and the rest of the NL Central) away down the stretch in two of the last three seasons, for one thing. They also have the 3rd best record in the NL and are basically knotted with Atlanta for second-best run differential.
It's just that they happen to be chasing the best record in baseball (for now).
The Cardinals' advantage might not be so much the fact that they have a more talented 25-man roster. Because I'm not so sure they do, under normal circumstances. By pythag record, the Reds are 2 games behind the Cards (as opposed to 3) and they're a series sweep away from being even. But the Cards seem to have more depth to pull from - both on the bench and on the farm.
I wanted to see if this idea of a shallow bench held up:
In raw numbers of quality major league starters, the Reds look a little thin. But Pedro Villareal's start yesterday was mostly an accident of Cueto's sudden flare-up and the way Fortuna's wheel of starters turned at AAA. The team currently has six starting pitchers who have put up a 107 ERA+ or better over 33 or more innings. They don't have a "fifth starter" because everyone has been pitching like a 4th or better. And the sheer quality of starters, not the least being Cingrani, has papered over Cueto's injury - while giving the team a little room for, say, some weak starts on getaway days.
If another starter beyond Cueto went down, it might not be pretty. But Armando Galarraga is pitching well enough (and has major league experience) that he could at least fake it through a few spot starts. And there's always Aroldis Chapman, I mean Sam Lecure, I mean Bronson making two starts-per-turn?
Here's where we get into the weeds. On the bench, Izturis and Hannahan are basically reprising the 2012 Cairo and Valdez routine, with Izturis hitting a hilarious .145/.232/.161. As far as the 40-man is concerned, it's Henry Rodriguez and Neftali Soto. H-Rod has hit better of late and could be a decent fill-in at 2B or 3B over a short spell, though the defensive drop-off at 2B would be serious. Soto probably wouldn't hit as well. But if he becomes the starter at a corner infield spot - which means either Votto or Frazier+Hannahan+H-Rod have gone down - then the Reds have a problem that a simple call-up won't solve.
Luckily, if the offensively productive infield starters stay healthy, having a weak bench won't matter much at all. It didn't last year.
I think the team is in better shape than they look here. Despite losing Ludwick early - and possibly until August or beyond - they've managed. Xavier Paul is OPSing .820 - which is better than half the starting lineup. Derrick Robinson has gotten on base at a better clip than anyone this side of Votto and Choo. That's a productive platoon, with Chris Heisey returning at some point and hopefully also Ludwick before the end of the season.
Paul wouldn't be nearly as effective as a full time starter (not shielded from lefties). But unless Robinson and Paul were both injured, while Heisey and Ludwick stayed injured, there wouldn't be a full-on outfield crisis. And the fact that Frazier can play LF and Choo is comfortable in RF is a bonus.
Things are messier in the bullpen. If fully healthy, the Reds' relief staff should be in the Top 5 in the bigs. But Sean Marshall is on the shelf again, Broxton has been ineffective and the Manny Parra signing is looking more and more like a bust. So depth becomes more important. Ondrusek and Arredondo looked like solid reinforcements entering the season. But Ondrusek is up with the team and has been mediocre, while Arreondo seems to be on the outs with the team and still can't find the strikezone in Louisville.
That leaves a smattering of unproven minor league arms. Justin Freeman is probably the best-performing relief arm at AAA and currently has a spot on the 40-man. Armando Galarraga could always pitch in relief, though his stuff may not play up in the bullpen. Yohan Pino has pitched well for the Bats, but he's a 29-year-old minor league journeyman. Chad Rogers could be plucked from AA (it happened to Jordan Smith). Loek van Mil is still the tallest player in professional baseball, as far as I know.
There are a decent number of options here, but it's possible that none of them would be remotely effective in the majors right now. We don't usually like it when the team overpays for relief pitching with prospects, but going to get someone at the deadline is starting to sound like a good idea. It shouldn't be too difficult to find a guy that at least improves the low end of the bullpen.
This is called the Low End Theory.