The Boston Celtics are set to commemorate their NBA Championship victory by raising their 18th banner at TD Garden before their season opener against the New York Knicks. Players will receive their championship rings during the pregame ceremony, which is expected to draw attendance from Celtics legends like Paul Pierce and Kevin Garnett. Coach Joe Mazzulla, the youngest coach to win an NBA championship since Bill Russell, emphasizes the need to maintain focus on the new season despite the celebratory occasion. While the Celtics are returning their core lineup, including All-Stars Jayson Tatum and Jaylen Brown, they acknowledge the challenge of quickly shifting their mindset from celebration to competition. The emotional ceremony is poised to reflect on the arduous journey to the title, as players like Al Horford express gratitude and anticipation for the upcoming season. The Knicks aim to disrupt the festivities with their revamped roster, adding another layer of excitement to the opening night.