For MLB playoff teams, which flaws will prove fatal?

It's a rite of October for fans to fret over the perceived weaknesses of their favorite teams — the ones who actually were good enough to make the playoffs.

But this is a year in which it's not easy to find managers and front office personnel striding confidently into the postseason, a field that provides the best example yet of retiring Commissioner Bud Selig's quest for parity.

There's no great roster among the 10 teams in a tourney that begins today, no overwhelming "team to beat." Good teams? Certainly, including some that didn't even reach the postseason.

Great teams? As Atlanta manager Fredi Gonzalez said while his team was still in contention, "We see the warts and pimples."

And all the remaining teams have them to varying degrees.

So, how do those warts and pimples affect the complexion of the playoffs? Here's a team-by-team list — in order of best record — of what to worry about most:

American League

Los Angeles Angels: A few good arms?

Seldom has a team with the best record over the regular season looked so vulnerable. The second half of the season among AL contenders was mostly about collecting enough pitchers to be competitive in October. The Angels addressed significant bullpen issues, and that turned out to be crucial to running away with the AL West, but attrition has chipped away at a rotation that was at least adequate. Postseason success could hinge on the starters behind No.1 Jered Weaver, who's solid but not quite at the level of some of the dominant Nos.1 and 2 in the AL. Garrett Richards was 13-4 when he was lost for the season. Matt Shoemaker was 14-3 as a starter but hasn't pitched since Sept.15 because of a stomach muscle injury. Shoemaker hopes to be ready for Game3 of the Division Series. It's not a question of whether it's more important to have a healthy Shoemaker or a dependable C.J. Wilson — the Angels need both. Wilson has nine starts of five or more runs this year and has gotten into the seventh inning in four of his last 16 starts.

Baltimore Orioles: Swings and misses

They're the major league home run leaders, and neither style nor history is on their side. Once since 1984 has the team that led the majors in home runs won the World Series (the 2009 New York Yankees). And 13 of the last 18 teams that led in homers didn't even make the playoffs. The Orioles are an example of what makes those types of teams more vulnerable to the big-time pitching they're likely to face in October. Baltimore swings at the most pitches outside the strike zone of any AL playoff team and makes the least overall contact of any playoff team in either league. And their hitters' walk-to-strikeout ratio is the worst among the 10 playoff teams. Does all that really translate to trouble against top teams? Well, the Orioles are batting .241 against power pitchers (those ranked among the top third in the league in strikeouts). That's 37 points lower than against finesse pitchers. And this season, Baltimore is batting .219 against the other AL playoff teams with a .341 slugging percentage. Overall, they're hitting .256 and slugging .422. The offense really could disappear.

Detroit Tigers: No relief, no D

The bullpen issues have been a season-long saga — closer Joe Nathan has even felt compelled to make a concerted effort to have a civil relationship with fans. That's what a 4.26 team ERA from the seventh inning on can do, not to mention a 1.49 WHIP (28th in the majors) against the first batters faced by Tigers relievers. But there's more contributing to how things go wrong later in games — the pitchers don't have a lot of margin for error. The Tigers are the worst defensive team in the playoffs, ranking 28th or 29th in the majors in all the various metrics measuring defensive range and efficiency. Third baseman Nick Castellanos and outfielders Torii Hunter, Rajai Davis and J.D. Martinez all have significantly negative Ultimate Zone Ratings. The Tigers can hit and pitch with power but fundamentally solid teams can "out-baseball" Detroit.

Kansas City Royals: Power outage

A short playoff series — even if the franchise's first postseason in 29 years lasts beyond today's wild-card game against the Oakland Athletics — is no time to have an offensive cold streak; this team is vulnerable to exactly that. The Royals were second in the AL in batting average but ninth in runs, led the major leagues in stolen bases but are the only team still looking for its 100th home run. They have four of the AL's top 13 players in infield hits. Their speed can produce pressure, but more important is whether being new to the postseason applies too much pressure on them.

Oakland Athletics: Sinkholes in the lineup

The same problems that turned a dream season into a mad scramble just to make the playoffs remain in play. You can debate whether trading Yoenis Cespedes to get Jon Lester is the actual reason, but the results are plain. A team that was batting .253 and slugging .432 on Aug.1 hit .225 and slugged .331 the rest of the season. Manager Bob Melvin scrambled with little success to solve the issue. Josh Donaldson batted third all of September, but since Aug.31, Oakland has tried seven players in the No.2 spot, five cleanup hitters and six each in the fifth and sixth slots.

National League

Washington Nationals: Those final nine outs

Nobody around this team wants to hear about 2012 anymore. Fairly or not, the Nationals' only playoff appearance defines a team that was on the rise then and looks all that and more this year. If there's one nagging issue, it has been the late-season meltdown of closer Rafael Soriano, which in more ways than one is connected to losing that '12 Division Series to the St.Louis Cardinals. Drew Storen was the closer then, and he's the closer now. In between, Soriano was signed before the 2013 season began — creating more depth was the official line, but lurking below the surface was that Storen lost his job. Statistically, there's no issue now. Storen has a 1.12 ERA this season. He hasn't allowed an earned run or a walk in the 11 games since he became closer again. All that said, does this team have demons from giving up the lead in that Game5? Does Storen? Was that merely part of a young team growing into the powerhouse the franchise remains confident it's building? There's no way to be certain about any of that until the next couple of weeks.

Los Angeles Dodgers: The Big 2, then who?

The 1-2 starting combination of Clayton Kershaw and Zack Greinke and closer Kenley Jansen is solid enough to get them through a five-game series. A longer series can create more questions, especially because No.3 starter Hyun-Jin Ryu is dealing with shoulder soreness. Whenever he's ready to contribute in the postseason, it would be his first start in at least three weeks. The other available options have combined for a 4.46 ERA in starts. The other pitching pressure point could be the mostly veteran group getting the ball to Jansen. Brian Wilson and Chris Perez both have ERAs above 4.00. The team ERA of 3.97 in the eighth inning ranks 24th.

St. Louis Cardinals: In search of a big hit

The Cardinals got to the World Series last year with a team that thrived on big hits in big moments; they're more ordinary this year, and that has translated into a difficult division race they couldn't seal until the final day. Who would have thought shortstop Jhonny Peralta would enter the playoffs as a crucial offensive player? Yes, the guy St.Louis plucked off the performance-enhancing-drug suspension scrap heap last offseason leads the team with 21 homers and is tops among regulars in late and close situations with a .301 average and 13 homers. The problem? Emerging players who took a step back. Matt Carpenter's batting average dropped 46 points, and his OPS 123 points. Powerful Matt Adams became the regular first baseman, which meant 244 more plate appearances than in 2013. He hit two fewer homers, and his walk-strikeout rate deteriorated by 25%.

Pittsburgh Pirates: Trouble out of blocks

Twenty-four blown saves are a concern, but the real fear is a rotation that ranks 13th in the NL in WAR. Edinson Volquez — who will start the wild-card game — and Francisco Liriano have combined for 17 starts of five or fewer innings this season. Those clunkers are as damaging as bullpens coughing up leads.

San Francisco Giants: Chasing trouble

Only the Colorado Rockies swing at more pitches out of the strike zone, and Giants third baseman Pablo Sandoval leads the majors swinging at 48% of the non-strikes he sees. The burden on Hunter Pence and Buster Posey might be too heavy.

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