It was the Trail Blazers' worst loss of the season. Damian Lillard had 20 points, Dorell Wright scored 17 and Wesley Matthews ended with 15 in the defeat for Portland.
"We have to do a better job, but overall, they just played a better game than us," said Lillard, who has scored at least 20 points in eight straight games and is averaging 24.0 ppg in that time.
The Blazers again played without All-Star forward LaMarcus Aldridge because of back ailment and he is out for Monday's game. Aldridge hasn't played since March 12 and is averaging 23.4 points and 11.1 rebounds.
Portland, losers in six of nine games overall, is 1-5 in its last six road games, 19-16 outside the Rose City and will also visit Orlando, Atlanta on Chicago on the trip.
The Heat have won two straight and three of four games against Portland, which is 4-1 in its last five trips to south Florida.