Jayson Tatum scored 46 points in Game 6 as the Celtics beat Giannis Antetokounmpo and the Bucks to force Game 7 in Boston. Morry Gash/Associated Press

MILWAUKEE — After surviving an elimination game Friday against the Bucks, the Celtics explained the key to their survival was how fast they moved on mentally from a crushing Game 5 loss days earlier.

Now, they’re turning the page just as quickly to Game 7.

“It means everything. The best atmosphere in the NBA,” Celtics forward Jayson Tatum said of returning to TD Garden. “Game 7s are the biggest and best games. So (I’m) looking forward to it, truly. Just winning this game, giving ourselves a chance to go back. And this is it. Do or die. It’s going to be fun.”

Tatum’s 46 points in Game 6, a signature performance for the rising superstar, overshadowed a bounce-back effort from Marcus Smart, who scored 21 of his own. Smart has played in three Game 7s as a Celtic, tied for most on the team with Jaylen Brown and Al Horford. Together, Smart, Brown and Horford won Game 7 showdowns over the Bucks and Wizards in 2017, after Horford had already played in three do-or-die playoff games earlier in his career.

“Man, it means a lot. It means a lot. It’s going to be loud,” Smart said Friday night. “I’ve had a few Game 7s in Boston, and I just understand and know that being in the Garden is not a place you want to be on the road in Game 7.”

The Celtics dropped their last Game 7, an 87-79 tussle with the Cavaliers in the 2018 Eastern Conference finals dominated by LeBron James. Tatum fouled out that night, while going head-to-head with James and racking up a team-high 24 points. Brown was held to 13 points on an off shooting night, though that memory is far from his mind heading into Sunday’s tip-off.

“I expect it to be loud, I expect it to be fun, and I expect to be part of a great game,” Brown said. “I’m looking forward to it. (The) best two words in basketball are Game 7.”

Because they remain one game from elimination, the Celtics intend to keep the same focus they did entering Game 6. Not only ignoring the past, but playing with an edge that furnished a fast start in Milwaukee and ultimately allowed them to return home to the Garden.

“You’ve got to come out with the mindset like kill or be killed. Survival of the fittest,” Brown said. “We don’t want to be the team or feel like we should be the team that is going home. You come out, put your best foot forward, leave the past in the past and do the best job to execute in the next game.”

HOURS AFTER describing Celtics center Robert Williams as “day-to-day” Friday night, Coach Ime Udoka repeated himself Saturday morning when looking ahead to Game 7 on Sunday.

During a video conference with reporters, Udoka said Williams’ knee injury is a matter of pain tolerance. On Friday, he revealed Williams suffered a bone bruise from a Game 3 collision with Bucks star Giannis Antetokounmpo and added the team wouldn’t return Williams to the floor until he felt 100%.

The Celtics have gone 2-1 in Williams’ absence, though Antetokounmpo has ravaged the paint without his rim protection.

Williams, 24, also offered a decent option against Antetokounmpo when the 6-foot-11 MVP forced switches early in the series. In Game 6, Marcus Smart matched up with Antetokounmpo more than any other Celtic and allowed him to score 12 points on 5-of-11 shooting, plus one turnover, according to NBA tracking data; a stark contrast from the 1-of-7 shooting Smart allowed Antetokounmpo’s teammates combined.