There’s something frighteningly special about the way nearly 19,000 fans scream their lungs out at opposing teams who face the Celtics at the TD Garden.

Home-court advantage has long been discussed as a crucially vital key to success in the NBA and the numbers behind the phenomenon don’t lie. The Celtics continued their unbeaten streak at home this postseason with a 114-112 win over the Philadelphia 76ers.

After winning the first two games at home and stealing a game on the road in Philly, the Celtics found themselves in good company: There’s never been a team in the NBA that’s blown a 3-0 lead in a series, ever.

But after blowing a chance to sweep Philly in a physical Game 4 that saw Boston lose yet another player to injury, the team was anxious to put the series with the Sixers behind them on the familiar floors of the Garden’s parquet.

“We didn’t want to go back to Philly,” said Jaylen Brown, who finished the night with 24 points. “We didn’t want to keep building their momentum, and it was good to get a close out game here on our home floor.”

The crowd at the TD Garden was on edge for most of the night, waiting for Boston to bust open a comfortable lead that never seemed to materialize. Time and again, when the Celtics would find a way to pull ahead, the Sixers would claw their way out of the hole.

“Any time we got any semblance of a lead or cushion they crushed it right away,” said Celtics coach Brad Stevens.

Still, when it mattered most, the Celtics pulled through, just like they have throughout the playoffs. With under a minute left, they stood strong, forcing the Sixers into costly turnovers and hitting free throws.

“You know, it was a taxing game for us,” said Center Al Horford, who was almost too tired to answer questions during the post-game press conference. “We left it all out there.”

This Philly-Boston series has seen old wounds open once again between two of the NBA’s most storied franchises. It’s a rivalry rich with young, still developing talent.

But in their next series, the Celtics will face off against another old friend. LeBron James has won 23 straight Eastern Conference playoff games, and he’ll be looking to extend that streak when he leads the Cleveland Cavaliers into Boston on Sunday to tipoff this year’s series.

Over the past decade, the Celtics have been something of a litmus test for King James. It was the Celtics who ended LeBron’s first run with the Cavaliers in 2010, and it was against the Celtics that James, with his back against the wall, put together an all-time classic Game 6 performance in the 2012 Eastern Conference Finals to cement his status as The Chosen One.

Now, it’s James who is the standard by which others measure themselves. The Celtics fell short against the Cavs in last year’s Eastern Conference finals and re-arranged their entire roster to subvert Cleveland’s authority as the premier team in the East.

But now that the drama of a showdown between former teammates has been taken off the table due to Kyrie Irving's injuries, it will be up to what’s left of the Celtics to take on Boston’s basketball foil.

The Celtics waited a whole year to get another shot at LeBron, and he’s somehow looking even better than before. They’ve taken on teams with blossoming superstars like Ben Simmons and Giannis Antetokounmpo, but that’s nothing compared to what lies ahead. As Boston surely knows, no king gives up his kingdom without a fight.

So far, the Celtics have out-coached, out-played and, in the case of TD Garden’s crowd, out-yelled their opponents into series victories. If the Celtics want a shot at hurdling over Cleveland for a spot in the NBA Finals, they’ll need every advantage they can get.