No. 5 starters are like opinions: Everybody's got one.

We do, I must admit before going one moment longer, attribute excessive meaning to excessively arbitrary labels. We fawn over Opening Day starting pitchers, even though many of them will not, in the end, be their team's best starters. We also obsess over No. 5 starters, even many of them won't still be starting halfway through the season, while a few others will have established themselves as rotation mainstays.

Still, I find those arbitrary labels endlessly fascinating (go ahead, sue me). So I've made a list of all the No. 5 starters, and yes it's fascinating (to me) and I've categorized them and now I'm going to share everything with you, from least common to most common ...

Barry Zitos (1)
San Francisco Giants (Barry Zito)

There's only one Barry Zito, man.

Bartolo Colons (1)
Oakland Athletics (Bartolo Colon)

Bizarrely, Bartolo Colon. Colon didn't begin the season in the Athletics' rotation, because he was busy serving out his 50-game suspension. Oddly, the A's re-signed Colon last winter. Well, it wasn't all that odd, considering Colon can probably still pitch some and it's only $3 million. Still, when Colon's one-game fill-in struck out 11 Astros the other day with nary a walk, it did look a little weird when the A's immediately sent him to Sacramento.

Are you kidding me? (2)
Los Angeles Dodgers
Washington Nationals (Ross Detwiler)

Detwiler could start for anybody in the majors. Meanwhile, even after trading Aaron Harang, the Dodgers still go six or seven deep in their rotation. I'm not even sure who their No. 5 guy would be. Definitely not Clayton Kershaw or Zack Greinke, and the other three rotationeers are Josh Beckett, Chad Billingsley, and South Korean rookie Hyun-Jin Ryu. Those guys could all pitch for almost anybody (well, maybe not Beckett and the Red Sox).

Grade-A Prospects (5)
Braves (Julio Teheran)
Cardinals (Shelby Miller)
Diamondbacks (Patrick Corbin)
Indians (Trevor Bauer)
Marlins (Jose Fernandez)

Corbin's not a rookie any more, but in my mind he's still a prospect. The other guys are all Rookie of the Year candidates, although Bauer's been dispatched to the minors after walking seven in his Indians debut. Then again, you might describe Carlos Carrasco or Scott Kazmir as the Indians' No. 5 starter, depending on the day of the week. This is a highly fluid situation ... and so fascinating.

Grade B Prospects (5)
Mariners (Brandon Maurer)
Orioles (Chris Tillman)
Pirates (Jeff Locke)
Rangers (Nick Tepesch)
Twins (Pedro Hernandez)

Feel free to quibble with any of these, but in the cases of Bauer and Tillman, the bloom's come off the rose some, and none of the other guys are generally considered top prospects.

Young Veterans (6)
Angels (Tommy Hanson)
Tigers (Rick Porcello)
Reds (Mike Leake)
Brewers (Mike Fiers)
Padres (Tyson Ross)
Yankees (Phil Hughes)

Chronologically, Porcello's the Tigers' No. 3 starter, with Max Scherzer No. 5. But that's not an accurate reflection of management's opinion; Porcello beat out Drew Smyly for the last job in the rotation, and there's been some speculation that Porcello got the job because the Tigers are showcasing Porcello for a trade. Either way, for now the Tigers are exceptionally deep in starting pitchers.

Old Veterans (10)
Astros (Erik Bedard)
Blue Jays (J.A. Happ)
Cubs (Carlos Villanueva)
Mets (Aaron Laffey)
Phillies (John Lannan)
Rays (Roberto Hernandez)
Red Sox (John Lackey)
Rockies (Jon Garland)
Royals (Luis Mendoza)
White Sox (Dylan Axelrod)

Technically speaking, Robert Hernandez (who used to be Fausto Carmona) is the Rays' No. 3 starter, but that's just a quirk in the spring scheduling or something; Alex Cobb is the Rays' No. 5 starter, but the Rays can't really have entered 2013 thinking that Hernandez-who-used-to-be-Carmona is better than Cobb.

Lackey's a special case, if only because he's the only one here making $15.25 million. But about the best you can say about Lackey is two or three of these guys will have a good season, and he might be one of them.

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