Then I could simply throw the challenge flag when the other team has a breakaway and kill their advantage. A goal is easily worth losing a substitution.
in football, you can't challenge a "no-call." essentially, the ref would have to blow his whistle: call foul, yellow card, or team scores a goal, whatever. so, play would already be "stopped," and there would be no potential for a breakaway in situations that a challenge flag could be thrown.
also (and just throwing this out there), has the larger soccer community realized yet that play stops plenty of times in a soccer game? It's just that the clock keeps running. The clock apparently has nothing to do with play. Is the clock in a soccer game "the opiate for the masses?" As long as the fans see it running, they are happy enough to believe that the game is continuous and uninterrupted?
hell, even stoppage time is non-sacred. There could be 3 minutes added, yet the ref may just blow the whistle and end things after 2 minutes, or 2.5 minutes, or maybe 3.7 minutes. According to what the announcers have said in the games that I've seen, it's really all at the center ref's whim when the game ends. ....WTH is that all about?
seriously, I'm curious if there's a legit argument for that.....