The Boston Celtics managed to advance to the second round of the NBA playoffs after beating the Bulls 109-99 in game 7 on Saturday night.

“It was a long, grueling series. I thought this was one of the most mentally tough series I’ve ever been in,” Celtics star Paul Pierce said. “Thank goodness we were battle-tested and we were able to pull this out in seven games. … We still are the champs until somebody knocks us off.”

The young Bulls played the Celtics closer than anyone could have expected and they should be proud of how well they played throughout the series.

“We had a lot of young guys who went through it for the first time. I think that will help us in the future,” said Bulls coach Vinny Del Negro. “Whenever you can go through an experience like this, I think it’s only going to make you better. Knowing how the level of physicality goes up, knowing how playoff basketball is played. … It’s a great learning experience for us.”