But, before the market open for trading on 8/6/13 (Tuesday), MGM will report its quarterly earnings. Depending on the quarterly results and/or the forward guidance, the price of its stock can react positively or negatively. One could avoid the adverse price reaction to earnings surprises by taking off all bets on MGM until after earnings have been reported. As always, trade your plan.
(click the chart to get an enlarge view)

Disclosure: No position in MGM