One thing is clear: the availability of the best pitcher on the free agent market and his subsequent signing with Yankees just hasn't been discussed enough. Never mind the articles devoted to the topic, nor the StoryStreams, nor the reactions! They're hardly important or even relevant. What we need to know is: with the addition of Masahiro Tanaka, where does the Yankees rotation rate compared to the rest of the league?

Has he alone taken them from weak spot to strength? Let's take a look, keeping in mind that we're taking into account the rotations as they are today, knowing full well additions are likely to be made for some. It's also important to note that depth beyond the starting five is pertinent to the rankings.

They have everything... almost. It probably depends on your definition of an ace, but for me they lack one. Stephen Strasburg has that potential, and the only thing he's lacking is innings, topping out at 183 last season. Gio Gonzalez, Jordan Zimmermann, and the recently-acquired Doug Fister push them towards the top. It's fair to call Gonzalez and Zimmermann No. 2 types, and Fister isn't far off. The top four here offer a phenomenal mix of potential and reliability. They'll eat innings, rack up strikeouts, generate ground balls and limit home runs: all five of their projected starters allowed fewer than 20 home runs and were below the league average in home runs allowed per nine innings.

Washington was able to get a 3.60 ERA out of their starting rotation last season (seventh in the majors). That's before upgrading from Haren to Fister, and it included multiple starts from emergency call ups such as Tanner Roark, Taylor Jordan, and Ross Ohlendorf, among others, and most of whom performed quite well. Ross Detwiler is currently penciled into the fifth starter's spot and he's been effective when healthy these last few seasons. Even so, with Jordan and Roark waiting in the wings, this is a deep and talented rotation from one through five.

Photo credit: Kyle Terada-USA TODAY Sports

Speaking of Fister, the Tigers would probably top this list had they not dealt him for Ian Krol, Steve Lombardozzi, and Robbie Ray. That they still rank so highly speaks to the quality and depth that General Manager Dave Dombrowski has compiled in Detroit. Led by as dominant a duo as there is, the Detroit pitching staff features two aces, a strong No. 2 and competent back-end starters, all of whom are 30 or younger. Detroit's rotation led the league in innings pitched and strikeouts per nine innings (as well as strikeout-to-walk ratio); a potent combination. While a bunch of those innings were shipped off to the team above, they should be capably absorbed by Drew Smyly, up to a point. Smyly has been phenomenal as a reliever but, has only thrown 175⅓ innings over the last two seasons, which is a concern. There is an argument to be made that the sixth and seventh starters (Luke Putkonen and Jose Alvarez), combined with Smyly's lack of innings are reason to knock them down a notch or two. That argument holds some water, but the talent in the Tigers' front three is unparalleled throughout the majors with Verlander, Scherzer and Sanchez all ranking in the top seven in pitcher wins above replacement over the last three seasons. No one else can boast a trio with the talent and track record that compares to these three.

One can only hold a rotation that starts Clayton Kershaw and Zack Greinke down for so long. The dynamic top of the rotation is backed up by Hyun-jin Ryu coming off of a great rookie season and Dan Haren, who continues to allow home runs but still be effective -- in the second half, at any rate. The fifth spot is a problem, being nominally filled by Josh Beckett and his boom-or-bust habit for the moment.While Chad Billingsley could be back in the first half of the season, it's hard to count on him for much coming off of Tommy John surgery. Beyond Billingsley, there's the uninspiring group of Stephen Fife, Matt Magill and Zach Lee, with the last offering the most upside. Lee, a former first round pick, hasn't developed the front of the rotation upside one would hope for with a $5.25 million signing bonus, he still has four quality pitches and has made 38 starts at Double-A, all before turning 22. Maybe that's a fourth-starter type package, but he's got the poise and repertoire to pitch in the majors as soon as 2014. The Dodgers paced the majors in ERA as a rotation last season, with the difference between their top-ranked 3.13 ERA and St. Louis' second-ranked 3.42 representing a larger gap than that between St. Louis and the eighth-ranked Mets' 3.68. That rotation featured more than enough starts from Magill and Fife, and while this year's iteration might see more of the same, the weight of the top two factor in heavily here.

St. Louis boasts rotation depth that every other club can only dream of. Lance Lynn might not even crack this starting five after throwing 200-plus innings of sub-4.00 ERA ball. They can lose two or three pitchers and fill in without breaking stride, and yet they're fourth. Why? They have one of the best pitchers in baseball at the top of their rotation (Adam Wainwright) and young studs behind him. Yet there's no one that is a rock-solid No. 2 (for now), and as much depth as they have, they have a lot of question marks too. Can Shelby Miller hold up over a whole season? Was Michael Wacha pitching over his head down the stretch and in the playoffs in 2013? Or Joe Kelly for that matter? Can Jaime Garcia stay healthy? The answer might be that none of these questions matter unless all of them matter, thanks to the deep well of young talent they have on hand, but with youth comes inconsistency and that can occur no matter how many prospects you have.

Photo credit: Jamie Squire

These next three rotations have in common across-the-board depth without one pitcher towering above the rest. They are all five (or more) deep in quality starters and each boasts a possible ace-type pitcher. The Rays head the grouping because there's no "possible" about their ace -- except perhaps for the question of whether he will continue to be with the team. David Price is the best pitcher out of these three teams, and one can say that confidently even with Price coming off a down year that would have been an up year by anyone else's standards. His decline still came with a 3.33 ERA, and while he saw a marked drop in strikeouts (four percentage points), Price countered that with an almost equally sharp drop (3.7 percentage points) in walks. Backed by a quartet that features both youth and experience (every starter threw at least 120 major-league innings in 2013, none are older than 26), Price and Rays have a starting five that boasts veteran savvy and enough upside that if everything clicks, they could be the best rotation in baseball.

The Reds and Red Sox, share, aside from a color, a similarity in their rotations. Both lack a true number-one starter, but both are extremely deep and feature pitchers that pitch at ace levels for stretches at a time. The Reds put together the third-best rotation ERA in the majors last year, just a tick behind the Rays at 3.43. They did this despite featuring one of the worst defensive center fielders in baseball (Shin-Soo Choo) and an unforgiving home park, as park factors rated Great American Ballpark second in the league when it comes to home runs. The back of their rotation features a question mark in Tony Cingrani, even though he was extremely impressive in his limited innings in 2013. The Red Sox, on the other hand, featured a rotation that ranked in the top eight in innings pitched, strikeouts per nine, and batting average against. Jon Lester leads a rotation that lacks an ace on the level of David Price but has enough depth to push Ryan Dempster out of the starting five. There's a chance that Clay Buchholz becomes that ace if he can put together a 200-inning season while performing at the same level that he did in 2013. Add in the continuation of the John Lackey revival tour and a full season of Jake Peavy, and the Red Sox have a rotation that carries both consistently above-average pitching as well as a breakout candidate.

The Braves and A's represent the next step down from the trio above. They have the same type of depth (perhaps more in Oakland's case) but lack the same type of potential impact starter on the order of a Latos or Buchholz. While Scott Kazmir is unlikely to pitch a full season, this is a team that received 44⅔ innings of 6.04 ERA ball from their on-paper number two starter last season (Brett Anderson), and Kazmir can surely best that. The A's also have the depth to withstand any injury time that Kazmir might accrue. Yes, there's a dropoff between Kazmir and Drew Pomeranz or Tommy Milone, but if Kazmir can give the A's 150 or so innings, as he did the Indians last year, the remaining frames that Pomeranz/Milone absorb won't be so impactful. While Straily and Griffin might not be inspiring, the fact remains their solid floors are better than those of a majority of back-end starters. Atlanta is in a similar boat, featuring impressive starters throughout their rotation from Mike Minor to Julio Teheran to Kris Medlen. The issue with Atlanta, the reason they rank behind Oakland, is depth. The Braves have Gavin Floyd, who should be available at some point in June, as well as a couple of options on the farm. Will it be enough to combat the injury/lack of innings risk that Brandon Beachy and Alex Wood represent? The Braves weathered injuries to Beachy and Hudson last season, but they had Paul Maholm to absorb some of these innings, as well as Wood coming out of the bullpen. With Wood in the rotation to begin the year now -- and Maholm and Hudson gone -- the Braves' depth is going to be tested once again.

And we finally reach the impetus of this article; and no it's not just because it's a convenient number. It was difficult to determine where to place the Yankees, because the upside of their top four is tremendous. That said, the downside of the fifth spot is a real issue. Yes, it's only one spot in their rotation, but it's representative of the lack of the depth the organization has. If any one of the top four starters get injured or need to miss significant time, that means that both David Phelps and Adam Warren will be in the rotation. If two starters miss time they're back to relying on Michael Pineda (a complete unknown at this point) or trying to coax Andy Pettitte out of retirement (again). That's a doomsday scenario of course, but contingency plans are of the utmost importance when it comes to starting pitching, and the potential downside of the Yankees rotation weighs heavily in this ranking. The lack of a true ace also plays a role, as CC Sabathia's best attribute is the innings he can absorb. Of course, when those innings come with a 4.58 ERA, it suddenly becomes something of a negative. With Sabathia's continued decline in velocity (he lost velocity on all of his pitches in 2013, per Brooks Baseball), paired with a decline in vertical movement, hoping for a return to his prior dominance problematic.

It's inevitable that comparisons will be drawn to the Rangers' Yu Darvish, given the country of origin and the money spent, but Tanaka more closely resembles the Yankees' own Hiroki Kuroda, featuring a splitter as a strikeout pitch as well as in build: Kuroda is 6'1/205 pounds, Tanaka is 6'2/205 pounds, while Darvish is a towering 6'5/225 pounds. If Tanaka can produce the same type of stat line as Kuroda has in New York, it's enough to push the Yankees into the top 10 rotations in baseball. There is some concern for the 38-year-old Kuroda, as he faltered badly down the stretch last season. Still, a 3.31 ERA over the course of a full season would be a welcome addition to any rotation, much less one that pitches in the AL East, where three of the five teams have ballparks that ranked in the top 10 run environments in 2013. While Phil Hughes' departure is a good thing, losing Pettitte might hurt this rotation as much as Tanaka helps (in the short term).

In all honesty, a ranking like this is premature; there are still free agents yet to sign that could change them dramatically. Still -- it's worth looking at how the balance of the league can be affected in the immediate aftermath of a singular signing (or trade for that matter). It can lack the perspective that we gain with hindsight but looking at the move in of itself allows us to evaluate it on it's own merits. Perhaps another team will sign Ervin Santana or Ubaldo Jimenez, negating some of the league-wide gains that it appears the Yankees have made with this signing. At the moment of the signing though, it propelled them from a bottom-third rotation to a top-third rotation, and that's worth talking about.

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