Unable to control his rage, Star-Lord begins to repeatedly punch Thanos in the head, which wakes him up just in time to catch the Gauntlet as it is slipping off his wrist.
Unfortunately, Star-Lord uses this opportunity to gloat, and it reveals an ugly truth: that Thanos killed Gamora in exchange for the Soul Stone.
After that moment, the good guys ultimately don’t get a win for the entire rest of the movie, and it dooms half of existence.
Using their combined powers and abilities, the heroes manage to lull the Mad Titan into a light sleep, and very nearly manage to get the Infinity Gauntlet off of his hand.