To steal some sports-martial language from my confessor, who has a "weakness" for such things, we're at war with Satan. Christ has secured victory in the end, but only (necessarily) in the end. In the world, at some point, that guy lying on the canvas is gonna be you. Gonna be me. There will always be defeats, as St. Josemaria warned us. But, my confessor also notes, a boxer shows his heart by whether he gets up and fights through a shellacking, not whether he ever takes one (all do).
Boxing is a sport, so the fight has time limits and a way to contrive a final outcome. But the fight of life and against Satan never ends as long as we are alive. Which has both a down and an up side. The down side obviously is that, for the standing fighter (in that pic FWIW, British light-middleweight champ Jamie Moore), victory is never total or complete. The upside is the flip side of that -- defeat is never final or total for the downed man (challenger Matthew Macklin). This particular fight was over that night, going into the books as a 10th round KO loss for Macklin, who reportedly was out cold for five minutes and stretchered out of the ring to a hospital.
The highlights of this "fight of the year" candidate are here, and here's the whole 9th round -- and they indicate why Macklin was counted out. It certainly wasn't that he didn't have the heart to fight through a shellacking. Quite the contrary; the fight had been such a slugfest for nine rounds that when he came out for the 10th, he had nothing left and crumbled when Moore landed a good combination that was no harder than a hundred other punches landed earlier in the fight.
Therein lies the difference for the sacramental life, if viewed properly, which is that we have God in our corner and all the Saints cheering us. Between every round, if we ask Him and receive His Sacraments, God renews us and restores us to the condition we were in at the start of the fight. Corner men can do wonders, but they are not God; and End-Swell is not the Body and Blood of Christ. We can be spiritually renewed every day as Macklin's body (or any other fighter's) could not be renewed every round. So we can fight every round as if it were the first. There is not (or should not be) any "accumulation of punches." There is not (or should not be) any "running out of gas." Our bruises should subside. Our cuts should close. Our broken nose should be back in joint and no longer impede our breathing. Our ribs and gut shouldn't ache from the punches taken nine rounds ago and since.
I've often stayed on the deck from fear of continuing to fight (meaning, "take more punches") ... or perhaps more accurately, I've fled back to the dressing room to whimper. But at some point in your life, you simply acknowledge that God is God and so leaving the ring/surrender is not an option. (Nor is trying to change the rules of the fight, so it's more to your liking.) Like Cortez burning his ships, we remove the ring-steps and aisles that could let us flee the arena. I have declared war on Satan, and so my only option is to fight on. Even if that means getting KO'd, over and over by a demon who has my number and whom I cannot lick. Obviously, the idea is to lick Satan, not the other way round. Hopefully, we learn something of how to fight from the shellackings. But remember that when you (let God) win, you (and God) win; if we lose, we still win because, as long as we're faithful, God will never count us out and declare the fight over.
Seconds out, round 11.