With a few exceptions, regular starters on Dusty Baker-led teams gets at least a little time off. There haven't been any completists who have lived up to, say, Justin Morneau's 163 season in 2008. (Considering Morneau's injury troubles since 2008, being an iron horse is not all it's cracked up to be).
Rest is good. In moderation.
Here are the players who have started more than 150 games every year since Dusty took over:
2012: No one
2011: Joey Votto (159), Jay Bruce (151)
2010: Brandon Phillips (151)
2009: Brandon Phillips (150)
2008: No one
A lot of this is health and instability, some of it is Baker's forbearance, but it's also a subtle reminder that backups become starters.
Scheduled rest usually means a good player gets tagged out by a worse player from the bench, but the good player in question might still be available to pinch hit or something. But if that same good player hits the disabled list, especially for more than a few weeks, it gets murkier.
Looking over the depth chart, I tried to figure out who would be spelling each of the Opening Day starters - and who might be tapped to replace them over a long absence.
Spot starter: Jack Hannahan (lefty bat) or Todd Frazier (righty bat). It's nice that the Reds have some flexibility here. Depending on the match-up, Dusty could use handedness to decide who gets the spot start.
Unthinkable scenario starter: Todd Frazier. Being the stronger fielder, I would think Jack Hannahan would take 3rd base and Frazier would shift over to 1B, not unlike last season. But it might depend on how Neftali Soto is doing. Or maybe even Henry Rodriguez is up to at 3B. It's cold comfort, but they can just pick the best corner infielder and then put Frazier at the other position.
Spot starter: Cesar Izturis, Jason Donald or Emmanuel Burriss. Whoever makes the team. Hannahan has played a little middle infield in the majors, but only has 2 innings at 2B.
Unthinkable scenario starter: Henry Rodriguez. Phillips is not as valuable as Votto, but as a 2B he's arguably harder to replace internally. I'm not sure we can count Jack Hannahan or Todd Frazier as 2B, despite their experience in the minors. Now that Billy Hamilton is a center fielder, Henry Rodriguez is really the only other second baseman on the roster who isn't also a back-up SS. But if they don't trust his glove enough, it'll be Izturis/Donald/Burriss. A creative solution might also be to pretend Billy Hamilton is an infielder again.
Spot starter: [Cut 'n' paste] Cesar Izturis, Jason Donald or Emmanuel Burriss. Whoever makes the team. Hannahan has played a little middle infield in the majors, but only has 24 innings at SS.
Unthinkable scenario starter: Probably one of those three guys. I can half-imagine Billy Hamilton moving back to play 2B in a catastrophe, but can't get my head around him coming up this season to play SS on a contending team. I'm not sure they'd trust Donald's glove enough to make him the primary SS either, even if he makes the team. The Reds would be in a bind to find a better-than-replacement option if Cozart went down, so I'm guessing they'd circle their wagons and play the glove guy.
Spot starter: Jack Hannahan. He was signed to an unnecessary 2 year contract to be the back-up corner infielder. So back up that corner infield.
Unthinkable scenario starter: I would guess it's still Hannahan, though there are some rumblings about Soto moving back to 3B. Henry Rodriguez would probably be the next in line though.
Unless there's a grass-borne plague that sweeps through GABP, it's going to be Heisey coming up everywhere, with a little Xavier Paul mixed in. In the second half of the season, though, Billy Hamilton and possibly Donald Lutz could be deputized.
The spot starter is either Olivo or Mesoraco, though I still don't really think Meso's job is in real danger. We don't know if Olivo would stick around if he doesn't make the team, though he gets above-league-minimum if he's called up. Especially with the way he's looked so far in Spring, I think Mesoraco is the answer to all of the above. He might even claw his way to a 50/50 playing time split as the season wears on.