A decision early in the game proved critical, and the Sixers never recovered in Game 4 as the Celtics rained on Joel Embiid's return to take a 3-1 series lead. Here are six thoughts on the game. The backup center minutes go to Drummond The Sixers were pulling their weight for the first six minutes and 49 seconds of the game, and then Nick Nurse pulled the wooden block that caused the Jenga tower to collapse on the spot. With Embiid available, he opted for Andre Drummond in the first stint of backup center minutes. Both teams struggled mightily to start the game. Boston, mind you, opened 0-for-4 from 3 with no made jumpers through Embiid's first stretch of minutes. Enter Drummond, who usually has to be married to drop coverage on defense. He promptly fouled Luka Garza, putting a Boston free throw on the board. 41 seconds after the Sixers started having to defend below the level of the screen because Drummond was on the floor, Payton Pritchard drilled a 3.…