In coming weeks, you will have innumerable opportunities to read previews of the upcoming season. I dug through last year's results and came up with items for each team that you probably won't see in the previews but that I thought were interesting.
I started with the National League (here, here, and here). Let's take the American League, west to east.
Oakland Athletics, 96-66: I don't know what to make of this, but something's going on with the A's and fly balls. Roughly speaking, of all batted balls, 45% are ground balls, 20% are line drives, and 35% are fly balls. Every team in the majors hit at least 40% ground balls...except Oakland, which was also the only team to hit more fly balls than ground balls. Same thing with pitching: Every staff in the majors had at least 40% of all batted balls hit on the ground...except Oakland, which was also the only team whose pitchers allowed more fly balls than ground balls. Over the winter, researcher Andrew Koo hypothesized that Oakland GM Billy Beane of Moneyball fame was exploiting a market inefficiency by recruiting fly ball hitters. (Original research here for Baseball Prospectus subscribers, summarized here.) But if it's true that fly ball hitters have an advantage in a game increasingly dominated by ground ball pitchers, what's up with the fly ball pitchers? Beane knows, I don't, and the A's have won the most games in the AL over the past two years, so it's obviously working.
Texas Rangers, 91-72: The most celebrated free-agent signing of last season was Josh Hamilton, who went from the Rangers to the Angels amid a fair amount of bitterness and recriminations. In 2012, the Rangers led the league in center fielder OPS, .870, with Hamilton getting 55% of plate appearances. They also led the league in left fielder OPS, .899. David Murphy was the primary left fielder, but Hamilton got 34% of plate appearances there as well. In 2013, without Hamilton, Rangers center fielders had a .719 OPS, just tenth in the league, and their left fielders were ninth at .722. Hamilton was a disappointment in Anaheim, with a .250/.307/.432 slash line and 21 homers after hitting .285/.354/.577 with 43 bombs in 2012, but his .739 OPS was still better than what the Rangers trotted out at his old positions last year.
Los Angeles Angels, 78-84: The Angels had some weird situational hitting splits. Angels batters advanced 58% of runners on second with no outs, third best in the league. They drove in 54% of runners from third with fewer than two outs, the best in the league. But with runners on first and fewer than two outs, they hit into double plays 13% of the time, the worst in the league. So they were great with runners on second and third but terrible with runners on first.
Seattle Mariners, 71-91: Not a lot went right for the Mariners, but their decision before the season to bring in the fences at Safeco Field worked. In 2012, Mariners batters hit 56 home runs at home, fewest in the league. In 2013 they had 88, the fourth most. Of course, the fences were brought in for the Mariners' opponents too, but the Mariners pitchers went from giving up 60 at home in 2012 to 82 in 2013. They hit 32 more and gave up just 22 more at home.
Houston Astros, 51-111: When you're looking for fun facts, the Astros are pretty target-rich. Worst record in the majors. Ended the season with a 15-game losing streak. New record for strikeouts in a season. Last in OPS and ERA. But if I had to pick one, it's this: The Astros were winning 56 games after seven innings. They wound up losing 17 of them. That's a .696 winning percentage, the worst in baseball. Just give them a league-average record holding leads after seven and they'd have won eight more games. Their bullpen was last in the league in ERA and last in strikeouts despite pitching the third-most innings.