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We're nearing the end of May, and nobody's running away with the American League.

Drat. I guess that means it's up to us to figure which team is the one to beat.

One thing we do know is that—at least until the Los Angeles Angels win, like, two more games—the discussion is focused on three teams: the Detroit Tigers, Oakland A's and Toronto Blue Jays.

With the the Blue Jays on a nine-game winning streak and the Tigers securing a split in their four-game series with the A's with a 5-4 win in Oakland Thursday afternoon, the three clubs are presently bunched at the top of the AL like so:

The Top of the American League Standings Team Record Win Pct GB Detroit 30-20 .600 - Toronto 32-22 .593 - Oakland 32-22 .593 - ESPN.com

There they are in all their glory, but which of these clubs is really the best of the bunch?

Run differential prefers the A's, as they lead MLB with a ridiculous plus-100 differential. Baseball-Reference.com's Simple Rating System—which measures how many runs per game better than average teams are—also prefers the A's, favoring them above all others heading into Thursday's action.

As baseball geeks, however, it falls on us to do a deeper dive. Let's do that by seeing how the Tigers, A's and Blue Jays stack up offensively, defensively, starting pitching-ly and relief pitching-ly.

Offense

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If we go off runs scored, the Blue Jays and A's began Thursday at the top of the AL, with the Tigers off their pace by about 40 runs. The Tigers did, however, begin the day trailing only the Blue Jays in OPS.

So let's ask a different question: Which offense is the scariest?

We can use OPS+ as guideline. That's a park- and league-adjusted version of OPS that puts everything on a scale where 100 is average. Anything above that, naturally, is above average, so OPS+ can tell us how many quality hitters each team has and precisely how quality they are.

As of the start of Thursday's action, here's a look at each team's nine most oft-used hitters:

Offensive Depth of Tigers, A's and Blue Jays Tigers A's Blue Jays Player OPS+ Player OPS+ Player OPS+ Victor Martinez 169 Brandon Moss 161 Adam Lind 169 Miguel Cabrera 146 Derek Norris 158 Jose Bautista 165 Ian Kinsler 118 Josh Donaldson 154 Juan Francisco 158 Torii Hunter 114 John Jaso 147 Edwin Encarnacion 148 Rajai Davis 107 Yoenis Cespedes 122 Melky Cabrera 134 Alex Avila 106 Coco Crisp 106 Jose Reyes 107 Austin Jackson 98 Jed Lowrie 104 Colby Rasmus 104 Nick Castellanos 71 Alberto Callaspo 93 Brett Lawrie 91 Andrew Romine 41 Josh Reddick 74 Dioner Navarro 80 Average 108 124 128 Baseball-Reference.com

The Tigers look less awesome here. Miguel Cabrera and Victor Martinez make for a fantastic duo, but there's a steep drop after them. And in all, Detroit has six above-average regulars to Oakland's and Toronto's seven.

But between the two, it's Toronto's lineup that looks stronger. There are more big numbers there, and more big numbers are always good where offense is concerned.

And even if Adam Lind and Juan Francisco tail off, it's a solid bet based on their track records that the trade-off will be Colby Rasmus (when he gets healthy) and Jose Reyes heating up eventually. Plus, the Blue Jays will have a one-two punch to match Cabrera and Martinez if Jose Bautista stays healthy and Edwin Encarnacion stays hot.

To the latter end, Bautista likes what he's seeing, telling MLB Network Radio:

Also, not pictured is how the Blue Jays have three reserves (Josh Thole, Steven Tolleson and Anthony Gose) with an OPS+ well north of 100. Also, FanGraphs has the Blue Jays outpacing the Tigers and A's in Baserunning Runs Above Average, which measures what it sounds like it measures.

So that Toronto offense? Oh yeah, it's pretty darn good.

Rankin' 'Em: Blue Jays, A's, Tigers

Defense

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OK, look. This being defense, AKA the white whale of baseball analysis, there's no perfect way to end this discussion with a perfect conclusion.

However, we can get at least a solid conclusion using Defensive Efficiency.

That's a Baseball Prospectus specialty, and there's no wizardry involved in it. All it does it calculate how good teams are converting batted balls into outs.

And for our three clubs, we find:

Defensive Efficiency of Tigers, A's and Blue Jays Split Tigers A's Blue Jays Figure .699 .742 .698 MLB Rank T-19 1 T-21 Baseball Prospectus

Full disclosure: Yeah, I'm moderately surprised to see the A's rating that well.

But only moderately. We don't tend to think of the A's as a defensive team, but they have two excellent defenders in Josh Donaldson and Josh Reddick, quality defenders in Eric Sogard and Yoenis Cespedes and two good defensive reserves in Craig Gentry and Nick Punto.

The best defensive team in MLB? Eh, I don't know about that.

But better than the Tigers and Blue Jays? That's easy enough to buy, sure.

Detroit is a better defensive team now that it no longer has Cabrera and Prince Fielder on the same infield, but it's still short on impact defenders. The Blue Jays are much the same, especially at a time when the defensive metrics (via FanGraphs) are lukewarm on Brett Lawrie and down on Rasmus.

So let's call it a push on the two of them and place them hand-in-hand behind the A's.

Rankin' 'Em: A's, Tigers/Blue Jays

Starting Pitching

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It's pretty clear cut which club's starting pitching ERA likes the most. The A's entered Thursday leading the AL in starters' ERA at 2.83, easily topping the Tigers (3.64) and Blue Jays (3.75).

But let's not take ERA's word for it. Let's take SIERA's word for it instead.

That's Skill-Interactive ERA, and it's not as complicated as it sounds. Per Baseball Prospectus, all it does is estimate what an ERA should be by focusing on strikeout rate, walk rate and ground-ball rate. In doing so, it does a good job of narrowing pitching effectiveness down to hittability.

And in looking at each team's top starters, we find:

Starting Pitching SIERAs of Tigers, A's and Blue Jays Tigers A's Blue Jays Player SIERA Player SIERA Player SIERA Max Scherzer 3.08 Jesse Chavez 3.16 Drew Hutchison 3.79 Anibal Sanchez 3.51 Drew Pomeranz 3.28 J.A. Happ 4.26 Rick Porcello 3.70 Scott Kazmir 3.46 Mark Buehrle 4.32 Drew Smyly 4.31 Sonny Gray 3.50 R.A. Dickey 4.37 Justin Verlander 4.67 Tommy Milone 4.57 Brandon Morrow 4.37 Average 3.85 3.59 4.22 FanGraphs

Those A's, man. They just can't stop looking good.

Yes, they still look good if we ignore Drew Pomeranz and his four-start sample size.

I wouldn't take any two of Oakland's top starters over Max Scherzer and Anibal Sanchez—they're awfully good and battle-tested to boot—but Oakland's trio of Sonny Gray, Scott Kazmir and Jesse Chavez is still a good match for Scherzer, Sanchez and (the much-improved) Rick Porcello.

Things would look different if Justin Verlander was still Justin Verlander, but he's not. His SIERA is up for a reason, as his strikeout rate is down, his walk rate is up and his ground-ball rate is less than sky-high.

It's also hard to ignore how much Verlander's fastball velocity is declining, which Jeff Sullivan of FanGraphs rightfully pointed out as something the 2011 Cy Young and MVP winner hasn't adjusted to yet.

Regarding the Blue Jays, their starting pitching still doesn't look great even if we buy that Mark Buerhle's 2.33 ERA is legit. Because even if we do that, their rotation is still a crap shoot after him and Drew Hutchison. R.A. Dickey is unpredictable, and then there's a big, steaming pile of "meh."

I'll call it a push between the Tigers and A's, and then Toronto.

Rankin' 'Em: Detroit/Oakland, Toronto

Relief Pitching

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Here's another place where ERA really likes the A's, as their relievers entered Thursday with the AL's second-best ERA at 2.88. The Tigers and Blue Jays entered the day with relief ERAs in the 4.00s.

But we can't stop there. While using ERA to judge starters is tricky, it's flat-out stupid to use it to judge relievers.

So let's go back to our friend SIERA and look at where each team's five most oft-used relievers—plus closer Casey Janssen in Toronto's case—stand:

Relief Pitcher SIERAs of Tigers, A's and Blue Jays Tigers A's Blue Jays Player SIERA Player SIERA Player SIERA Joba Chamberlain 2.23 Sean Doolittle 1.44 Brett Cecil 2.73 Al Alburquerque 2.36 Luke Gregerson 2.55 Esmil Rogers 3.29 Evan Reed 2.97 Fernando Abad 3.00 Casey Janssen 3.49 Joe Nathan 3.45 Dan Otero 3.52 Sergio Santos 3.55 Ian Krol 3.91 Jim Johnson 4.13 Aaron Loup 4.11 Steve Delabar 4.32 Average 2.98 2.93 3.58 FanGraphs

Hey, suddenly Detroit's bullpen doesn't look so bad.

And that's warranted. Joba Chamberlain, Al Alburquerque and Evan Reed all have strong strikeout-to-walk ratios, and Chamberlain and Reed also boast ground-ball rates over 50 percent. That's a solid bridge to Joe Nathan, who has indeed pitched better than his 4.58 ERA.

Meanwhile in Oakland, Sean Doolittle, Luke Gregerson and Fernando Abad are also rocking the K/BB game, and Gregerson and Abad have ground-ball rates in the neighborhood of 50 percent. And while Jim Johnson has been a disappointment, it bodes well that his SIERA says he doesn't deserve a 6.00 ERA.

As for Toronto's pen, it's not a bad pen. It just isn't that good, which is owed largely to the walk rates of its top relievers. With Janssen being a notable exception, five of the six are walking more than three batters per nine innings. Four of those five are walking over 4.5 per nine innings.

Just like with the starting pitching discussion, it's too close to call between Detroit and Oakland. Ryan Cook's potential return to form once he gets healthy is certainly an X-factor, but let's avoid betting on that and call it a push between the two of them with Toronto once again bringing up the rear.

Rankin' 'Em: Detroit/Oakland, Toronto

Verdict Time

Long story short: Yeah, the A's are pretty good.

The best way to look at the A's is as the Tigers with a better offense and defense. Heck, they look even better if you buy what ERA has to say about their bullpen and their starting rotation, which looks like a good match with Detroit's for a change.

The decline of Justin Verlander is the big factor there. Take him out of the equation, and the A's likely advance to the American League Championship Series in 2012 and 2013. That he looks like he's out of the equation this year, then, is something the A's must be thrilled about.

Don't count out the Tigers, of course. They're a great team, and the general suckitude of the AL Central gives them an easy path to October.

Don't count out the Blue Jays either. They may be all offense, but, hey, that offense is mighty good.

But two months into the 2014 season, it's the A's who have all you can ask for in a contender.

Note: Stats courtesy of Baseball-Reference.com unless otherwise noted/linked.

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