In winning the negotiating rights to Yu Darvish, the Texas Rangers fired back at the Angels’ own busy offseason. The news also rattled the city of Toronto, flooding phone lines and Twitter with bitter disappointment after the Jays’ own run at the Japanese star. But you know who should be sweating the most right about now?

Red Sox Nation.

For the past five seasons, the American League wild-card slot has been granted to AL East teams, as if by divine right. The Red Sox won 96 games in 2007, ending the Yankees’ nine-year run as AL East champs. But the Bombers still won the wild card with ease that year, topping the Angels and Tigers by six games apiece. The next year, the Tampa Bay Rays came out of nowhere, winning 97 games to win the division … which was no problem for the Red Sox and their 95-win, wild-card-clinching season. 2009? The Yankees and Red Sox both glided into the playoffs. 2010? Yankees and Rays. 2011? Yankees and Rays.

Now, the full-on arms race being waged by the Rangers and Angels threatens to leave Boston out of the postseason for the third straight year, with other hopeful contenders set up to meet the same fate.

The Angels fired the first shot at the end of the winter meetings, nabbing Albert Pujols and C.J. Wilson on the same day. Those moves shocked the baseball world, with Pujols believed to be headed to Miami or back to St. Louis. They also reaffirmed the notion that big-revenue teams could shake off massive financial mistakes in a way that small-market clubs can’t begin to imagine (we see you, Vernon Wells). Having lost Wilson to their biggest rival and having made no significant offseason additions save for a $14 million flier on a rehabbed Joe Nathan, the Rangers saw their two straight AL West titles (and AL pennants) in jeopardy and felt they needed to make a move. Of course, it made sense for the Rangers to pursue Darvish even before they knew what would happen to Wilson: Just as the Angels play in a huge market with a monstrous new TV contract on the way, so does Texas.

Projecting any Japanese League pitcher is tough, even one with Darvish’s credentials. We’ve talked about the different hitters and ballparks, the six-man rotation instead of five, and other factors, including pitch counts that can sometimes run higher for elite pitchers in Japan than they do for North American aces. Still, scouts have raved about Darvish’s natural talent, broad repertoire, and durability. The Rangers are getting a 25-year-old starter with a great track record, bolstering a rotation that’s now so deep we could see a very good pitcher like Alexi Ogando or Matt Harrison get relegated to the bullpen. That pitching depth complements a lineup so loaded, the Rangers’ best postseason hitters this fall often hit out of the seven and eight slots (granted, curious lineup construction had something to do with that). The lineup is still overloaded with right-handed hitters, and Prince Fielder would make all kinds of sense as a huge upgrade over Mitch Moreland. But if the Rangers stand pat from here, we’ve got two strong candidates to surge past 90-plus wins in the AL West next season. Maybe even 95.

All of which leaves the AL’s good-but-not-quite-great teams in a bind. The Red Sox were a much better club in 2011 than they showed during their September collapse. But that doesn’t change the fact that they could really use a reliable three- or four-win starter, plus maybe a bat for right field if Ryan Kalish isn’t ready yet. The Rays badly need viable bats at first base and DH. The Indians are an intriguing sleeper team, but a rotation stuffed with worm burners and a few promising, young bats probably won’t be enough in the fortified American League.

Meanwhile, the Mariners and A’s are in even worse shape. Seattle has a top-heavy roster with cornerstone players in Felix Hernandez, Michael Pineda, and Dustin Ackley, and a whole lot of questions marks in the majors and the minors. The A’s are aggressively shopping several established players this offseason, which would make perfect sense as a way to reload for the future if the players they were marketing weren’t so young themselves. Oakland’s return for Trevor Cahill looks light even in MLB’s new prospect bubble. Cahill and Gio Gonzalez were seen as keys to the next winning A’s team just a year ago, before turning into trade chips being leveraged for the next window of opportunity. That window might come in 2014, 2015 … or when Mike Gallego’s great-grandkids swoop in on winged stallions and take over the world. The Mariners play in a good-sized market with plenty of revenue potential of their own, while the A’s have gotten a smidge of attention for their front-office smarts. But you can’t help but wonder if both teams could find themselves in the Orioles’ spot for the next several years, looking up with envy at better, richer teams.

The extra wild-card spot could eventually help Seattle and Oakland. It could offer a more immediate boost to the suddenly endangered powers in the AL East, as well as the upstart Jays. But 10 months from now, we might very well see Yu Darvish facing Albert Pujols, with AL supremacy and a trip to the World Series in the offing.

And may God have mercy on the Houston Astros’ souls.

Jonah Keri’s new book, The Extra 2%: How Wall Street Strategies Took a Major League Baseball Team from Worst to First, is a national best-seller. Follow him on Twitter at @JonahKeri.

Previously from Jonah Keri:

Who Do ‘Yu’ Think Your Are?

Who Should Sign Prince Fielder?
What Do We Really Know About Ryan Braun?

Read more of The Triangle, Grantland’s sports blog.

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