With Hiroki Kuroda's decision to return to Japan and forgo another chance to don the pinstripes, the Yankees have one fewer option to flesh out their rotation. As it stands, they will presumably have Masahiro Tanaka, Michael Pineda, CC Sabathia, Nathan Eovaldi, and Chris Capuano making up the Opening Day rotation, with Ivan Nova set to return sometime in the middle of the year. They've lost David Phelps, who, while never spectacular, did give them at least a bit of depth and starting experience out of the bullpen, and midseason acquisition Brandon McCarthy (who many of us hoped Brian Cashman would bring back), has been taken off the board, snatched away by the Los Angeles Dodgers. Adding Kuroda or McCarthy would've given the Yankees the depth they'll need if they hope to compete next year, but with those options no longer available, the Yankees will have to turn elsewhere to finish building their rotation.
And no, giving Chris Capuano thirty-something starts next season is not the answer.
Internal options
Bryan Mitchell: Jason's done a deep dive on Mitchell here, but quickly, Mitchell is one of the only Yankee pitching prospects that might find his way into the rotation next season. He has long been raved about by scouts, as his pure stuff is some of the best in the Yankees system, but he's never been able to put it together in the minors. He's had control issues in the past, but he did show a little improvement in Triple-A last year, posting a 3.46 BB/9 in 41.2 innings. Overall, though, he wasn't particularly impressive in the minors last season, posting a 4.09 FIP in 61.1 Double-A innings and a 4.44 FIP in Triple-A. While he'll probably get a chance at some point in 2015, and his repertoire still shows some great upside, there's nothing in his history that suggests Mitchell will be a dependable or decent part of the Yankee rotation.
Manny Banuelos: Once seen as one of the best prospects in the Yankees system, Banuelos' value has fallen quite a bit since Tommy John surgery cost him the entire 2013 season. He did finally make it back onto the field in 2014, but the results weren't pretty: he posted a 4.59 ERA and 5.03 FIP in 49 innings in Double-A before posting a 5.56 FIP in a limited appearance in Scranton. While it's not clear if some of these struggles are just ManBan working the kinks out after a year off or if he's just not the pitcher he once was, Banuelos will certainly need more time in the minors before he's even conceivable as a legitimate option in the rotation.
Free agent options
Max Scherzer: Still the best option for making this a potentially stellar rotation (and giving the Yankees the kind of pitching/defense combination that could make them a great team even if their big bats don't rebound next season), but if they avoid him - and wisely continue staying far, far away from James Shields - there are a few other lesser free agent options still out there.
Ryan Vogelsong: He has spent the last four seasons with the San Francisco Giants and was ranked as the 38th best free agent of the offseason by MLB Trade Rumors. However, he hasn't had a decent year since 2012, posting a negative fWAR in 2013 and just 1.0 fWAR in 2014, when he pitched to the tune of a 4.00 ERA and a 3.85 FIP. He wouldn't put the Yankees over the top, but he'd be cheap and probably could be counted on to pitch at least 150 innings. He's pitched at least 179 innings in three of the four past seasons (and the only season he didn't reach that threshold he missed time due to a freak injury).
Aaron Harang: Another older pitcher, Harang could also add a little more certainty to the Yankees rotation without costing much. Harang was surprisingly effective in 2014, posting a 2.5 fWAR along with a 3.57 FIP in 204.1 innings with the Braves. However, he likely wouldn't be able to duplicate that success in 2015 - his HR/FB rate of 6.4% is unsustainable, given that his career rate is 10.2%, and his success came a bit out of nowhere, as he hadn't been anywhere close to as valuable since 2009.
Neither Harang nor Vogelsong project to be that much of an improvement over Capuano, and would just give the Yankees a glut of old, low-upside starters blocking any chance any prospect might have at seeing some major league action this year. The Yankees should stay away from these two, and any of the Paul Maholm/Chad Billingsley ilk.
Trade?
Jordan Zimmermann and Cole Hamels are names that have been floated about in recent days who some feel the Yankees could target, but the Yankees seem to be more interested recently in acquiring cheap, young talent with upside rather than giving it away. While Zimmermann would be nothing more than an expensive rental (too expensive for a team that will be looking at an uphill climb in 2015), Hamels will be under contract until 2018 and could be worth dumping some of the Yankees best prospects for.
Kuroda or McCarthy would have been exactly what they needed, but if the Yankees don't sign Scherzer or trade for Hamels, there is really no need to sign one of the cheap arms left on the market. Better to just hope the rotation stays healthy and give someone like Mitchell, Banuelos, or maybe even Adam Warren a chance when injuries strike. If nothing else, the front office can figure out what it has in some of its young arms, and either decide they can be part of the Yankees future, or hopefully determine their trade value to flip them at the right time.