Bosh had nine points in the first eight minutes of the second half as the Heat kept a fairly wide margin. But Portland closed in late when Matthews and Batum made back-to-back layups to make it 65-61. Norris Cole quieted the crowd by answering with a 3-pointer for the Heat.
Batum's 3-pointer and Matthew's fade-away jumper narrowed it to 82-79 with 4:53 left. After rookie Damian Lillard missed a couple of free throws, Batum made a layup and a free throw to tie it up.
"It's an understatement to say it's great to beat Miami. They're a great team, defending champs," Blazers coach Terry Stotts said. "I gotta hand it to our guys for sticking with it. You keep competition, playing through and finding a way to win games. That's kind of what we did tonight and kind of what we've been doing most of the season."
Lillard, the reigning repeat NBA Rookie of the Month, had 10 points and eight assists and became the first NBA player to make at least 75 3-pointers in his first 35 career games since Allen Iverson in 1996-97.
The Heat were without Shane Battier, who has a sore right hamstring. The move was proactive, coach Eric Spoelstra said before the game.
"It was never a strain, it's just very sore," he said. "But those things can be tricky."
It was the second of a six game road trip for the Heat, who fell to 7-8 on the road this season.
NOTES: Stotts was back after missing practice on Wednesday with a flu bug. Luckily, he said, his mother was visiting. "My wife was out of town so my mom took care of me," the coach said. ... The Heat signed forward Jarvis Varnado to a 10-day contract on Wednesday. Varnado played in five games earlier this season with the Boston Celtics, scoring six points in a total of 18 minutes. The Celtics waived him on Sunday. ... Portland rookie center Meyers Leonard is a ways off from returning from a sprained right ankle. "I wouldn't give him a timeline, but he's not close," Stotts said. ... Mariners pitcher Felix Hernandez was at the game.