if you have an unlimited bankroll, then martingdale can work.
Martingdale system works every single time except once: the time you go broke
A great quote from the wikipedia page on the martingdale system
"Since expectation is linear, the expected value of a series of bets is just the sum of the expected value of each bet. Since in such games of chance the bets are independent, the expectation of all bets are going to be the same, regardless of whether you had previous won or lost. In any gambling game, the expected value of any individual bet is going to be negative, so the sum of a bunch of negative numbers is also always going to be negative."
And as impossible as it seems for a sports team to lose 20 games in a row .... each game is still an independent event