The Celtics entered the season vowing to turn recent playoff heartbreaks into happiness.
Eight months later, they will toast the franchise’s 18th championship in what has become standard Boston celebratory fair, joined Friday by a huge crowd for a duck boat parade through the city to mark the 13th championship won this century by one of the city’s Big 4 professional sports franchises.
The Celtics, Patriots, Red Sox and Bruins have all commemorated championships in recent years by jumping aboard the boats — amphibious vehicles usually used to show tourists the town sights.
But in Boston, firing up the duck boats for a slow cruise down city streets has become synonymous with its feeling of sports supremacy.
It is the latest component of what has been a rolling salute to the team since it cemented itself as the kings of the NBA on Monday night when it finished off the Dallas Mavericks in five games in the final.
Set to start at TD Garden at 11 a.m., the procession was expected to last about 90 minutes, turning first onto Causeway Street in front of arena, past city hall, through Boston Common, down Boylston Street and eventually ending at Hynes Convention Center.
