Do not do this.
Splatoon did not have an overtime at first, and you know what happened? After a certain point, it was impossible for the losing team to come back and win. I was there. After a certain point, the winning team just stopped playing because they literally could not lose. It is the absolute worst feeling that, no matter what you do, even if you get a good rally, you cannot win. Overtime makes it so you have a chance for your hard work to turn it around. I've had games where we did turn it around in Overtime because the opponents got complacent.