At the end of last year, the Detroit Tigers had finished a healthy 15 games ahead of the second-place Cleveland Indians, but that race wasn't without some nail-biting in Detroit. Despite a strong 95-67 final record, the Tigers spent the first half of the season hovering just above .500 and didn't wake up in the morning in first place until the middle of June.
Detroit was heavily favored to repeat going into the season (and justifiably so), but the American League Central's looking like a real race rather than an extended warm-up for October. While winning the division seemed a real uphill climb for the Indians or Chicago White Sox back in March, several things that needed to happen to give the division's best also-rans a shot have started to come together.
So what made Detroit so vulnerable?
Dunn and Rios playing like major leaguers
Dunn and Chicago seemed a match made in heaven, with Dunn a perfect defensive player for designated hitter and U.S. Cellular Field a comfortable home for power hitters. While Dunn's low batting average, lots of walks and power profile suggested that he wouldn't age well, at 31 his decline should have still been a few years off. Instead, he had arguably the biggest drop-off year in baseball history (it was the biggest drop from two-year OPS going back to 1900), finishing the season slugging .277.
Rios had a similar stinker of a season, hitting .227 AVG/.265 OBP/.348 SLG and escaping notoriety only because of being overshadowed by Dunn's worse season.