NBA champion Celtics take Round 1 and end Cavaliers' perfect season after 15 straight wins

This was a chance for the undefeated Cleveland Cavaliers to see where they stood against the defending champions. “This was a great test for us, and unfortunately we didn’t get the win,” said Donovan Mitchell, whose 35 points couldn’t prevent the Cavaliers from picking up their first loss of the season, 120-117 to the Boston Celtics on Tuesday night. “It’s definitely a measuring stick,” said Mitchell, who scored 18 points in the fourth quarter, including 14 straight Cleveland points in the final four minutes.