Updated

It's never easy to make preseason predictions in baseball.

When no regular-season games have been played, it's difficult to determine exactly what effect each team's new acquisitions will have on their new squads. It's also impossible to predict which players will suffer significant injuries that could alter their respective teams' outlooks.

Now it's July, and we have the benefit of having watched more than half of the regular season. So it should be much easier to pick baseball's division winners, right?

Not necessarily. In the American League, all three division races are tight, and as many as 11 of the league's 15 teams are in the hunt for one of the three titles.

Let's try to use the evidence we've seen to determine a winner in each AL division race (we'll handicap the NL division races next week).

EAST DIVISION

This shapes up to be a tremendous race because all five teams have a realistic shot at a division title. Boston has gotten off to the best start, taking a 3 1/2-game lead over second-place Tampa Bay heading into Tuesday's action.

There's little question the Red Sox have been the division's best team to date. They have a plus-82 run differential for the season, which is easily better than those of Tampa Bay (plus-50), Baltimore (plus-22), the New York Yankees (minus-4) and Toronto (minus-6).

If Boston can solidify its shaky closer situation, it would have to be considered the favorite here. The Red Sox bullpen has blown 14 leads already. Compare that to the Yankees, for instance, who have blown only four. It's been the main factor in keeping injury-riddled New York in the race.

Baltimore made the playoffs last year on the strength of a potent young offense and one of the game's finest bullpens. This season, the Orioles' bullpen has blown 17 leads.

The Orioles' pitching staff in general has been one of the weakest in the AL, although the team traded for Scott Feldman last week and is rumored to be seeking more pitching help before the July 31 trade deadline. Baltimore will outhit many of its problems, but it will probably need to add a top-flight starting pitcher to emerge in this tough division.

There's a lot to like about Tampa Bay, which will benefit from the recent return from injury of pitching ace David Price. The biggest strike against the Rays, however, is a 20-24 record against AL East opponents.

Considering about half of a team's games are against divisional foes, Tampa Bay will need to dramatically improve that performance in the second half. Right after the All-Star break, Tampa Bay goes on a road trip to Toronto, Boston and New York. That stretch could go a long way toward determining the Rays' fate.

New York has the division's worst offense by far. It should improve when rehabbing superstars Derek Jeter and Alex Rodriguez finally make their season debuts, but Mark Teixeira is out for remainder of the season. Given the Yankees' usual dominance, it's hard to believe they would be the division's worst team if not for their outstanding bullpen and solid defense.

New York will almost certainly remain in striking distance of the division lead at the trading deadline, so there is always the chance it will add significant reinforcements. The usually free-spending Yankees have done so in the past. With their stated goal of staying under the luxury tax threshold, though, they may opt against making a big splash later this month.

Toronto was left for dead earlier this season. The Blue Jays were 11 games under .500 as recently as May 10 (23-34). Now they're 43-45, so they've been the hottest team in the division.

After slow individual starts, some of their key players, like pitcher R.A. Dickey, have righted the ship. Another top acquisition, shortstop Jose Reyes, has returned to the lineup after a long injury absence. If he can get on base consistently for the Jays' big boppers, this could be an interesting second- half team.

THE PICK: If Price can pitch like Price during the second half, TAMPA BAY has a real chance to sneak up and win baseball's best division. With hot prospect Wil Myers up with the team now, the Rays appear poised to make their move. The bullpen will have to improve in the second half, but the pitchers have the pre-2013 track record to be able to do just that.

CENTRAL DIVISION

For the second year in a row, prohibitive division favorite Detroit has underperformed and allowed other teams to hang around in the race. Heading into Tuesday's games, the Tigers hold a 3 1/2-game lead over second-place Cleveland.

The Tigers have a run differential of plus-92, which is easily the division's best (Cleveland is plus-14 and Kansas City is plus-8). So Detroit ought to be able to do what it did last year - go on a dominant second-half run and pull away for the division crown.

A roadblock in Detroit's path to another title, however, is an unsettled closer role. There figures to be a few closer candidates available at the trade deadline, and the Tigers will probably have to explore some of those options.

Cleveland has a fine young offense and below-average pitching. Thanks to several offseason moves, Kansas City boasts one of the AL's best pitching staffs, but its young and touted offense has not delivered.

Both are imperfect teams, but Cleveland has a chance if Ubaldo Jimenez can start to pitch like an ace. A disappointment since coming over from Colorado in 2011, he showed some promise in going 3-1 with a 3.09 ERA in June. Maybe he's turning the corner. On the other hand, he lasted fewer than six innings in six of his seven June starts.

Kansas City needs young hitters like Eric Hosmer and Mike Moustakas to begin living up to their potential. They have high upside, so it wouldn't be a complete surprise if the light switch turns on for both of them in the near future. It looks like it might have already started to happen for Hosmer.

During the preseason, Minnesota looked on paper to be one of the weakest teams in the majors. The Twins' 37-49 record is nothing special, but it's better than many would have expected.

Few thought the White Sox would threaten to finish last in the AL Central, but that's where they sit right now, 14 games out of first. A 9-17 record against divisional opponents makes it unlikely they could even play an effective spoiler role. They also have a few nice trade chips, so some of their best players could be headed out of town before August.

THE PICK: It might be a boring prediction, but DETROIT has the edge in talent and is also the team most likely to improve itself at the trade deadline. That combination should prove tough to beat, even though Cleveland and Kansas City are two of baseball's best up-and-coming teams.

WEST DIVISION

The Los Angeles Angels were the most popular preseason pick to win this division, thanks to the addition of prized free agent Josh Hamilton. He hasn't been the impact player most thought he'd be, as he's batting just .230 and 12 homers and 34 RBI.

The Angels were 15-27 on May 17. Since then, they've gone 28-18, seemingly putting them back into the race.

Hamilton's former team, the Texas Rangers, looked like a top-quality preseason team on paper, too. They've had one of the league's best pitching staffs, but the offense has only been in the middle of the pack.

Texas has a talented team that's only slightly underachieving in some areas. Elvis Andrus has been disappointing, as has Lance Berkman. Still, the Rangers are on pace for 95 wins, which is two more than they had when they lost the division to Oakland by one game in 2012.

Speaking of Oakland, despite a $60 million payroll that ranks among the bottom five in baseball, the Athletics are a contender to repeat as division champion. They are in first place, a half-game ahead of Texas. Moneyball strikes again, as closer Grant Balfour (a blatant All-Star snub), starter Bartolo Colon and third baseman Josh Donaldson rate among the best at their respective jobs and are among the league's bargains.

Fourth-place Seattle isn't going to win the division, but the Mariners have elite pitching at the minor-league level that, when combining with Felix Hernandez and Hisashi Iwakuma, will help make them an intriguing team in the near future.

Houston, despite being a pest to the Angels, is the worst team in baseball.

THE PICK: It would be hard to go against TEXAS, which is already one of the league's best teams and has the potential to improve its level of play. One also would suspect the Rangers would be more likely to take on a big salary at the trade deadline than Oakland, which should nevertheless stay in the hunt all the way.

The Angels are too talented to count out of this race. However, a division title seems remote only because it's unlikely that both the Rangers and Athletics will collapse.