The youth movement is alive and thriving for the Boston Celtics.

And for the second straight game it was enough to upend a Philadelphia 76ers team that still has much to figure out as it heads home trailing 2-0 in the Eastern Conference semifinals.

Rookie Jayson Tatum scored 21 points and hit a pair of free throws in the closing seconds Jason Witten Cowboys Jersey , helping the Celtics rally from a 22-point deficit to beat the 76ers 108-103 on Thursday night.

Terry Rozier added 20 points, nine assists and seven rebounds. Marcus Smart finished with 19 points and five rebounds as the Celtics improved to 6-0 at TD Garden this postseason. They have never blown a 2-0 lead.

”Coach was saying whoever is the tougher team is going to win,” Rozier said. ”They definitely punched us in the mouth at the beginning of the game. We just had to bounce back and get things together.”

Game 3 is Saturday in Philadelphia.

J.J. Redick had 23 points for the 76ers, making five 3-pointers. Robert Covington added 22 points and nine rebounds. Joel Embiid finished with 20 points, 14 rebounds and five assists, but rookie star Ben Simmons missed all four shots and had just one point.

”Mentally, just thinking too much,” Simmons said of his tough night. ”I’m going to have bad games. It happens. Obviously, it’s bad timing.”

Philadelphia recovered after squandering its big lead to nudge back in front 93-88 midway through the fourth quarter.

But an 11-4 run put Boston back in the lead 99-95 with less than four minutes to play.

It was 101-97 when a missed Philadelphia jumper led to a 2-on-1 fast break and alley-oop dunk from Rozier to Tatum with 2:23 left.

A layup by Dario Saric cut it to 104-101. But Al Horford was able to drive past Embiid for a layup with 8.3 seconds left.

Saric scored out of a timeout to make it 106-103. The Sixers quickly fouled Tatum, who calmly hit a pair of free throws.

Following an anemic offensive effort in Game 1, the Sixers looked rejuvenated early in Game 2, using a 14-2 run to begin the second quarter on their way to building a 48-26 lead.

It didn’t last.

The Celtics responded by ending the half on a 25-8 run. It included three straight 3-pointers and a tip-dunk by Jaylen Brown, who returned to action after sitting out the series opener with a strained right hamstring. He came off the bench and played 25 minutes, scoring 13 points and grabbing four rebounds.

The Sixers’ lead was completely erased midway through the third quarter Youth Joseph Noteboom Jersey , when Aron Baynes got a 3-pointer to bounce in and put Boston in front for the first time.

The lead grew to 76-68 on a baseline dunk by Tatum that capped a 50-20 Celtics run.

”Once we got on that run we never looked back,” Rozier said.

Brown entered the game for the first time at the 7:14 mark of first quarter. It took less than a minute to make an impact. He missed his first shot attempt before chasing down a loose ball and sprinting ahead for a one-handed dunk .

Prior to Thursday, Brown had started every game he’d appeared in this season. It was his first time off the bench since Game 5 of last season’s Eastern Conference Finals.

”They won two games at home and we have to reciprocate,” Sixers coach Brett Brown said. ”There’s not going to be a pity party.”

TIP-INS

76ers: Outrebounded the Celtics 49-41. … Went 13 of 33 from the 3-point line.

Celtics: The 22-point comeback victory represents their largest come-from-behind playoff victory since Game 4 of the 2008 NBA Finals (24 pts). … Went 15 of 36 from the 3-point line.

HE SAID IT

”It’s like a movie. You only see these type of comebacks in movies.” – Celtics guard Marcus Smart.

SLOW START

Despite Brown’s early highlight, the Celtics were sluggish early.

They started off the game 0 for 5 and didn’t score until Smart’s 3-pointer at the 8:37 mark of the first quarter.

Horford (1 for 3), Rozier (0 for 4), Brown (1 for 4) and Marcus Morris (0 for 3) were a combined 2 for 14 in the period, allowing Philadelphia to build a 31-22.

CELEB SIGHTINGS

Philadelphia-born rapper Meek Mill sat courtside for Game 2. Mill was released from jail last week after spending nearly five months behind bars on a probation violation. Rapper Gucci Mane sat across from the 76ers bench wearing a Brown jersey. The two met last year when Brown attended one of his concerts.

Another Philly native, actor Kevin Hart, sat a few seats down from Gucci. Hart at times antagonized the TD Garden fans, drawing boos.

—

No, Vance Joseph never felt as if he was drinking out of a firehose when the Denver Broncos stumbled through a 5-11 season in his first year as head coach last year.

That's how general manager John Elway has repeatedly described what it must have been like for a first-year head coach in the NFL.

"That's not my personality, so I didn't feel that way," Joseph told The Associated Press. "My focus was purely on trying to flip it and get us back on a winning path. I think being a young head coach and being a young coach is a different deal. I'm not a young coach. I've been a part of teams that have gone through adversity so I kind of knew what the issues were."

Turnovers.

A sieve of an offensive line.

Locker room rifts.

A lack of chemistry Andy Dalton Jersey , the byproduct of another protracted quarterback competition.

Still, "I think overwhelmed, that's not the word," Joseph said.

Denver's dive, which included eight losses by double digits, was a shock to a city and a franchise that had a ticker-tape parade just two years earlier, and Elway acknowledged that he pondered firing Joseph at season's end.

"That's the direction I want to go, but it's my responsibility to think about other options to see what would be best for the football team," Elway said in January. "We thought about different options, but ultimately, my goal was to stick with Vance and give him that shot."

Elway, who had riled up his players by calling them soft during an eight-game skid, said he shared in the blame for Joseph's deficient debut and needed to surround him with better personnel.

Joseph replaced nearly half of his coaching staff while Elway embarked on a massive roster upgrade .

He signed quarterback Case Keenum in free agency and all 10 members of his ballyhooed 2018 draft class spent four years in college and most were captains. That's a far cry from the previous two classes that were loaded with raw athleticism, long-term projects and plenty of question marks.

Joseph seems much more comfortable in his second season.

"I don't see it as a do-over. It's hard in this league. You don't get do-overs Roberto Perez Jersey , unfortunately. But it's a new year and obviously last year wasn't good enough," Joseph said.

The hands-off philosophy Joseph brought to Denver last year has vanished.

"I think it's a fine line between micromanaging and coaching coaches. And I didn't want to ever be micromanaged as an assistant coach because in my mind I was doing the best I could for that head coach and the best I could for that football team. And I took great pride in coaching my guys and being the best group on the field every day in the meeting rooms or on the field," Joseph said.

"So, in my mind every coach would feel that way and every coach would want to coach that way. So, I was cautious in interrupting coaches' drills, interrupting coaches' ways of doing things because I had an experienced staff."

That led to the notion that Joseph was still acting like an assistant coach last year while offensive coordinator Mike McCoy continued operating as though he were still a head coach before getting fired at midseason.

Joseph vehemently denies that was the case.

"I thought Mike did a great job every week of accepting his role and we talked every week about the game plan, so that's not true," Joseph said.

"I worked for a lot of coaches who didn't micromanage me, Gary Kubiak, Marvin Lewis, great guys who have won a lot of games. So, that's not true. Our staff last year we discussed every game plan that we put forward and again it was the best thing for our players at the time.

"So, our thought process early on was to be an explosive offense. We were 3-1. It wasn't perfect. But it was working. Now, turning the ball over Authentic Derick Brassard Jersey , not protecting the quarterback, those things affected how we played on offense. But not Mike trying to be in total control, that's not true."

Still, Joseph said he has to coach his coaches better, and by that, he means challenging them.

"I don't coach the receivers, I don't coach the running backs or offensive line. I'm a defensive backs guy, I'm a defensive guy. So, I think asking the right questions and triggering more thought process on how we can do things better. Or simply seeing it differently than the coach and saying, 'Why don't we do it that way?'" Joseph said.

"Now, I can be wrong, but I think simply asking more questions is a simple way of helping the coaches get better and helping our football team get better and not letting anything slide."

Joseph realizes he won't get another chance if things don't change.

"Winning football games is a must this year," he said. "We have to do that. That's why they hired me."

And why Elway stuck with him.

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