Zion Williamson revelled in the New Orleans Pelicans' rallying win over the Boston Celtics after the team completed their largest comeback in franchise history.

The Pelicans looked down and out against the Celtics but overturned a 24-point deficit to stun the visitors 120-115 in overtime in the NBA on Sunday.

Boston led 79-55 in the middle of the third quarter before Williamson, Brandon Ingram and Josh Hart (17 points, 10 rebounds, three blocks and a steal) got to work in New Orleans.

Ingram – who posted 33 points – nailed the go-ahead three-pointer with 33.3 seconds remaining in OT, while former number one draft pick Williamson scored 24 of his 28 points following half-time.

"I think it was about the will to want to win," said Williamson, who also recorded 10 rebounds, four assists and a block for the Pelicans.

"We just wanted to win. We didn't want to get blown out in our gym. We fought. We played hard. It didn't look smooth at first, but we figured it out and came up with a W."

"It was a big win for us because we stayed true to who we were," Williamson continued. "We rallied back. Everybody – coaches, players, ballboys – everybody was just engaged and we needed all that energy, and we pulled through."

Ingram added: "I think we can take away that we're really, really good when we stay together."

The Pelicans (13-17) narrowly avoided losing for the sixth time in seven games, and head coach Stan Van Gundy praised his team.

"I think the real lesson of this game for us is we beat a really good team," Van Gundy said. "We were far from perfect.

"There were a lot of things we didn't do well. But we kept fighting. Nobody dropped their heads. We were resilient. We came away with a win."