Miami's win, coupled with Milwaukee's loss at Philadelphia, assured the Heat a sixth-place finish in the Eastern Conference and a first-round series against the third-seeded Philadelphia 76ers.
Toronto (59-23) had long since clinched the East's No. 1 seed. The Raptors will begin the playoffs against the eighth-seeded Washington Wizards. Toronto came up short in its bid to win 60 regular-season games for the time in franchise history.
Ellington shot 12 of 16 from the field and 8 of 12 from 3-point range. James Johnson, Tyler Johnson, Kelly Olynyk, Justise Winslow and Dwyane Wade scored 11 points each for the Heat (44-38). Hassan Whiteside had a double-double with 10 points and 12 rebounds.
Miami took the lead for good on Bam Adebayo's three-point play 41 seconds into overtime.
Kyle Lowry led Toronto with 28 points, and he added 10 rebounds and nine assists. DeMar DeRozan scored 19 points, and Poeltl had 16 points and 12 boards.
Ellington's 3-pointer with 18.8 seconds remaining in regulation put Miami ahead 105-103. The Raptors tied it on Jakob Poeltl's tip-in off Delon Wright's missed 3-pointer with 8 seconds left.
Miami had an opportunity to win in regulation, but James Johnson's short jumper with one second remaining bounced off the rim.
Miami rallied from a double-digit deficit midway through the third quarter and took a 96-95 lead on Ellington's 3-pointer with 3:14 remaining in the fourth quarter.
Lowry's second of consecutive 3-pointers with 1:51 left tied it at 102-102. DeRozan's split two free throws with 1:26 remaining, putting Toronto ahead 103-102.
DeRozan's two free throws with 5:45 remaining in the third gave the Raptors their first double-digit margin at 70-59.
Miami began its comeback early in the fourth quarter and got to within 85-83 on Olynyk's layup with 7:17 remaining in the period.
DeRozan scored eight consecutive points, including a running floater from the right baseline at the buzzer, to give the Raptors a 53-47 lead at halftime.
--Field Level Media
Toronto | Miami | |
Kyle Lowry 28 | Scoring | Wayne Ellington 32 |
Kyle Lowry 9 | Assists | Kelly Olynyk 5 |
Jakob Poeltl 12 | Rebounds | Hassan Whiteside 12 |
DeMar DeRozan 7 | Free Throws Made | James Johnson 3 |
Jakob Poeltl 3 | Steals | Josh Richardson 2 |
Jonas Valanciunas 3 | Blocks | Hassan Whiteside 2 |
Team | Points | FG% | 3PM-3PA | FTM-FTA | Assists | Rebounds | Blocks | Steals | Turnovers |
Toronto | 109 | 45.7 | 9-30 | 16-21 | 24 | 47 | 10 | 5 | 14 |
Miami | 116 | 43.4 | 11-26 | 13-20 | 26 | 56 | 7 | 8 | 9 |