The Celtics had a fully healthy roster for the first time all season heading into Friday’s win over the Bulls, but that didn’t stop them from relying heavily on their sixth man when it mattered most. Payton Pritchard scored 19 of his season-high 29 points in the fourth quarter to help Boston to a 138-129 victory over Chicago on Friday night at the United Center. Overall, it was Boston’s seventh straight win, moving the team into the top spot in the East just half a game ahead of the Cavs. The win also kept the Celtics alive in the NBA Cup and kept the door open for a wild card spot thanks to Pritchard’s heroics.

The point guard knocked down seven 3s in his 28 minutes and played the final 19 minutes of the game after Derrick White was sidelined in the third quarter with a foot injury. He helped Boston take control of the game midway through the fourth quarter, scoring 11 straight points for the visitors in an 11-4 run to calm a Chicago crowd that believed the Bulls could win the NBA. Cup for the surprise.

“It’s a great feeling, of course, but the best feeling for me is winning on the road and being able to help my team overcome the crisis tonight,” Pritchard told reporters in Chicago, via NBC Sports Boston. “Obviously I feel it. I can hear the crowd, the gravity that pulls them. It was definitely a fun evening.”

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This scoring outburst was accompanied by Jayson Tatum (35 points) on the bench, who could only rave about his 1.90 meter tall teammate, who extended his sixth man of the year even further.

“I say all the time, me and P, same high school class, so I’ve seen that fearless competitive character since we were like 13,” Tatum told reporters. “It’s been pretty cool to see him develop into the player he is, how he’s effective on a championship team and what he’s doing makes him Sixth Man of the Year worthy for me.”

Pritchard scored 29 of the Celtics’ 34 points off the bench in the win and was one of six Celtics to score in double figures. As his minutes and role increase in his fifth NBA season, he’s grateful for the respect he’s earned from the more experienced members of the roster, but believes it’s due to one key thing.

“Through hard work,” Pritchard explained. “You see the hours I put in and that builds respect among my teammates. That’s how I get other people’s respect, but it’s also through my work that other people earn my respect.”

That hard work has led to the late first-round pick becoming a crucial part of Boston’s title core. Pritchard enters his first year on a four-year contract and remains eager to build on the best start of his career.

“Just having confidence, knowing you’re one of the best, and all the hard work and hours you put in over the summer, being able to come out every night and help the team win. I have a strong belief in myself and I feel like my teammates also believe in me that I can do it.”