Let me first state that I do not follow baseball, so I don't know if my odds estimates are accurate. I'll outline the structure of the hedge and then you can adjust it when lines come out later this morning.
The first thing you want to hedge against is a Detroit win coupled with a Twins loss today. Assuming the Tigers would be -150 and the Royals +200, a parlay of the two would give you +400.
Assuming you bet 1000/3500 on the Twins originally, you could bet the parlay to take away some or all of the risk involved in your bet. For instance,
...................Detroit.........Twins
..Bet.............Wins Div.......Win Div
...................Sunday.........Sunday
250/1000....EVEN...........+3250, protecting your original iinvestment
500/2000...+1000.........+2500
900/3600...+2600.........+2600
Some other amount could be wagered as well. It really depends on your tolerance for risk and whether or not the protection offered by the hedge is worth the price. There's more to the hedge, however.
If both teams meet with the same result today, the parlay loses and you would continue the hedge by playing Detroit at plus money against the Twins. The size of this bet would depend on how much your parlay bet was, and, of course, the odds on Detroit in the playoff game. One thing to notice. The numbers in the chart above are the results ONLY if the division is decided today. Any hedging done on the playoff game would eat into your profits further.