Philadelphia CEO Adam Aron tweeted at the break, "This will have to be one of the best come backs ever for the (at)Sixers."
Down 15 at the half, the under-25 Sixers found their spark, their legs and their shooting touch to crank up the pressure on the Celtics.
Williams hit a 3, Iguodala hit a 3, and Williams converted a three-point play to make it 58-54. Williams stood on the free-throw line with the widest smile of anyone in the building and calmly sank the deficit-slicing free throw.
Meeks, a starter-turned-sub, stole an errant pass and scored his first bucket of the game to make it 63-59 at the end of the quarter.
The 76ers' 10 baskets in the third were one more than their total for the entire half and their 28 points were three shy off their halftime total.
"We're just going to keep fighting," Collins said. "That's what we do."
The Sixers had vowed they would be a more determined team after the veteran Celtics dismantled and demoralized them on their home court in Game 3.
The Sixers said after the 16-point loss they would return more focused to prevent another hot Celtics' start that took them out of the game and sucked the atmosphere out of the Wells Fargo Center.
The Celtics squashed that attitude moments after the opening tip before thousands of fans had taken their seats.
Pierce and Avery Bradley hit 3-pointers, Garnett hit a pull-up 20-footer and the Celtics raced to a 14-0 lead only 3½ minutes into the game.
The Sixers truly couldn't find their footing. Young bounced the ball off his sneaker on a drive down the lane, and Pierce converted on the other end for an 18-3 lead.
The Celtics could never find that extra scoring boost to truly put away the Sixers. Rondo, Garnett and Allen all had quiet first 24 minutes and the Celtics let the lead drop to seven.
Rondo scored an uncontested bucket coming out of a timeout to end the half and put the Celtics up 46-31.
"That was probably the worst we could shoot," Iguodala said. "They were playing as good as they could play and we were shooting poorly."
Boy, did it ever work out in the end.
Notes: The 76ers are 4-1 at home in the postseason. ... The Sixers are 3-3 this postseason trailing by double-digits after a 5-23 mark in the regular season. ... The Sixers outscored Boston 34-26 in the paint.
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