Chris Sale is on the disabled list with shoulder inflammation, Trevor Bauer is out with a fractured fibula and James Paxton is still recovering from a line drive off his left forearm. At this stage of the season, every contender is dealing with injuries, and few are more worrisome than those afflicting their top starting pitchers. It's tough to imagine surviving the stretch run and playing deep into October without a rotation in top form, or at least with the depth to cover for those less-than-healthy hurlers.
With that in mind, and with a look at the FanGraphs playoff odds page and rest-of-season projections -- which are driven by the Steamer and ZiPS forecast systems and focus on the component skills (strikeout, walk and home-run rates) that make up the Fielding Independent Pitching (FIP) metric -- what follows is a quick snapshot of each contender's rotation as Labor Day, and the moment of truth, approaches.
American League
Ever since the A's surged past the Angels in late June, it's been clear that the AL playoff picture boils down to six teams fighting for five spots. But few imagined that two months later, Oakland would be battling for the AL West lead. Meanwhile, the Red Sox's four-game sweep of the Yankees in Fenway on Aug. 2-5 basically sealed the AL East, and the recent slides of the Yankees and Astros have opened up a few different permutations of the wild card.
Houston Astros
While their lineup has dealt with health issues, the Astros' durable five-man rotation (Justin Verlander, Gerrit Cole, Dallas Keuchel, Charlie Morton and Lance McCullers Jr.) covered the team's first 125 starts without giving one to an outsider. That iron-man streak finally ended when reliever Brad Peacock made a 1 2/3-inning "opener"-like start on Tuesday in place of McCullers, who strained a muscle in his elbow while swinging a bat on Aug. 4. As long as the rest of the unit continues to hum along -- and the projections say it will -- McCullers' absence into September isn't likely to be an issue.
Cleveland Indians
The much-improved Bauer (2.22 ERA, 2.38 FIP, 5.9 WAR) was a bona fide Cy Young contender until a line drive off his right leg on Aug. 11 caused a stress fracture in his fibula. He'll likely miss four to six weeks. With Cleveland unchallenged in the AL Central, our projections suggest he'll return for just a brief pre-playoff tuneup of five innings; as long as Corey Kluber and Carlos Carrasco remain in working order, that should be enough.
New York Yankees
If there's an AL rotation projection that looks too optimistic, it's this one. While Masahiro Tanaka is hitting his stride (2.54 ERA and 3.59 FIP over his last six starts) and J.A. Happ is a solid upgrade over Sonny Gray, Luis Severino's recent pummeling (7.02 ERA, 5.35 FIP, 0-for-8 in quality starts) makes it difficult to have much faith in his projection (3.32 ERA, 3.29 FIP, 1.1 WAR) going forward, and CC Sabathia's projection (4.46 ERA, 4.55 FIP) is as precarious as his arthritic right knee. A banged-up bullpen, with concerns about Aroldis Chapman's knee and David Robertson's shoulder, only adds to the worries facing this staff.
Boston Red Sox
Sale, the AL leader in ERA (1.97), FIP (1.95) and WAR (6.1), has allowed just one run in his last seven starts, totaling 44 innings, but he's now on his second DL stint for shoulder inflammation. His lone start between those stints was brilliant (five innings, one hit, 12 K's against the Orioles on Aug. 12) but the persistence of his woes is troubling. The Red Sox's cushion over the Yankees allows them to let Sale heal (take the under on our 35-inning projection for the rest of the season), but the drop-off to David Price (0.6 WAR projection) and Rick Porcello (0.5) is steep. The good news is that July acquisition Nathan Eovaldi's success with his new cutter makes him a good bet to outdo his projection (4.30 ERA, 4.06 FIP. 0.5 WAR).
Seattle Mariners
With a 17-24 record since July 4, the Mariners are fading, and with or without Paxton (who could return in time for next weekend's series with the A's), they lack the arms to arrest the slide, even if Mike Leake, Marco Gonzalez and Wade LeBlanc can continue to outpitch their modest projections. Given the performance of Felix Hernandez to date (5.75 ERA, 5.00 FIP), the M's need the briefly exiled King Felix to pitch like it's 2014. But alas there's no time machine in Safeco Field.
Oakland Athletics
If there's a culprit for a stolen time machine, it's the A's, because Trevor Cahill, Edwin Jackson and Brett Anderson -- all currently in Oakland's rotation, if you haven't paid attention -- are pitching like it's 2010. The trio already has combined for 3.5 WAR, 2.1 more than projected as of March. Cahill owns the staff's highest WAR (2.1), but given that he hasn't made 20 starts since 2013, his health and durability are always a concern. Still, Sean Manaea and Mike Fiers both appear likely to outpitch their 4.50-ish ERA projections down the stretch given their solid work to date.
National League
Divisions, wild-card spots -- quite simply, everything -- is up for grabs in the NL. If you're a fan of #TeamEntropy, the dream of needing more than 162 games to determine its playoff participants, this could be your year.
Los Angeles Dodgers
For the sputtering Dodgers (14-18 since the All-Star break), the real issue is a flimsy bullpen that's being propped up by the shifts of starters Kenta Maeda, Caleb Ferguson and the now-injured Ross Stripling. That still means the team is asking a lot of the effective-but-fragile corps behind Clayton Kershaw. While the team uses the DL as a roster-management tool, it can't be too comforted knowing that Rich Hill, Hyun-Jin Ryu, Alex Wood and rookie Walker Buehler all have multiyear streaks of suffering injuries, and any one of them could return to the DL, thereby exposing the bullpen again.
Arizona Diamondbacks
Zack Greinke may no longer be on Kershaw's level, but no NL rotation has a trio of starters who project as well over the rest of the year than Greinke (3.60 ERA, 3.57 FIP, 0.8 WAR), Robbie Ray (3.83 ERA, 3.70 FIP, 0.7 WAR) and Patrick Corbin (3.56 ERA, 3.47 FIP, 0.7 WAR). And given his reputation for on-again, off-again streakiness on an annual basis, it's reasonable to expect the resurgent Clay Buchholz (2.47 ERA, 3.61 FIP, 1.3 WAR in 73 IP before Wednesday night's sharp outing) to continue beating his unflattering projection (4.74 ERA, 4.44 FIP) down the stretch.
Philadelphia Phillies
Driven by the outstanding work of Aaron Nola (2.24 ERA, 2.73 FIP, 5.0 WAR), the Phillies' 14.5 WAR leads all NL rotations. While it would certainly help if Jake Arrieta (3.25 ERA, 3.84 FIP, 2.3 WAR) could recover his 2015 NL Cy Young form, the real question is whether Nick Pivetta and Vince Velasquez can maintain their stamina and performance as they head toward new highs in innings. Pivetta (129 1/3) has never thrown more than 148 2/3 in a season (2016 at two minor league stops), and Velazquez (124) hasn't topped the 136 he threw in the majors and minors that same season.
Chicago Cubs
Back in March, the Cubs projected to have the majors' fourth-best rotation, but thus far it's been the worst of any contender (4.12 ERA, 4.61 FIP, 4.6 WAR). Whether it's the cumulative burden of three straight trips to the postseason or a more contact-centric approach via new pitching coach Jim Hickey, holdovers Jon Lester, Kyle Hendricks and Jose Quintana have been subpar, to say nothing of free-agent additions Tyler Chatwood and the shelved-for-the-season Yu Darvish. Newcomer Cole Hamels and staff savior Mike Montgomery are the only ones immune, but now the latter is sidelined by shoulder inflammation.
Colorado Rockies
Nolan Arenado and Trevor Story aside, the Rockies are not very good at building a lineup, and they may as well have set the money spent on upgrading their bullpen on fire. Nonetheless, despite the myriad difficulties of pitching at high altitude, the Rockies have assembled a quality rotation, one that ranks fifth in WAR (11.4). Can Jon Gray, Kyle Freeland and German Marquez maintain their strong performances as they surpass their previous highs in innings? We're about to find out.
St. Louis Cardinals
The Cardinals' playoff odds have more than doubled since the firing of manager Mike Matheny, from 21.0 percent to 50.8 percent, despite getting just two starts from Carlos Martinez and none from Michael Wacha. With the former limited to bullpen duty due to his shoulder strain and the latter unlikely to return from his oblique strain before September, the pickings look pretty slim beyond the surprisingly solid contributions of Miles Mikolas and Jack Flaherty.
Atlanta Braves
No rotation in either league has a bigger gap between its ERA and FIP than the Braves (-0.52, via its 3.56 ERA and 4.08 FIP). Quite simply, their caliber of run prevention isn't very well supported by their peripherals, which is why their rotation's projection is so low. For as good as Mike Foltynewicz and Sean Newcomb have been, their projections going forward (0.5 and 0.4 WAR, respectively) don't inspire much confidence, particularly as they race past career highs in innings.
Milwaukee Brewers
Somehow, the Brewers are occupying the second NL wild-card spot despite a low-wattage rotation that ranks no better than ninth in the league in ERA, FIP or WAR. Given that none of their starters projects to provide more than 0.3 WAR the rest of the way, Milwaukee may well regret its failure to upgrade at the deadline. Hamels, Happ, Eovaldi -- any of them would have provided some improvement.