Eric Bledsoe and Jabari Parker scored 17 apiece and Thon Maker had 14 for Milwaukee, which now trails the best-of-seven series 2-1. The Bucks are seeking their first playoff series win since 2000-01, but they've never won a series after trailing 0-2.
"We came out (and) just wanted to be the first team that hit first (and) be physical," Middleton told ESPN after the game as confetti fell from the rafters. "The crowd was great tonight, they got us going."
Al Horford finished with 16 points, Greg Monroe scored 15 against his former team and Jayson Tatum had 14 for Boston. The Celtics won the first two games of the series, and they've never lost in the playoffs after doing so on 35 prior occasions.
Game 4 is Sunday afternoon in Milwaukee.
Parker, who averaged 12.6 points during the regular season, had been held to two points on 1-of-7 shooting over the first two games of the series.
Boston won Game 1, 113-107, in overtime and took Game 2 by a 120-106 result.
Milwaukee shot a blistering 57 percent (45 of 79) from the field while holding the Celtics to 40 percent shooting (32 of 80). Boston outrebounded the hosts 45-37.
Bucks starting center John Henson missed the game after being doubtful before tip-off with back soreness. Former Celtics big man Tyler Zeller started in his place and had two points and two rebounds in 19 minutes against his former team.
Milwaukee had its foot on the gas pedal from the start, building a 15-point lead after one quarter at 27-12. The Celtics missed 16 of their 18 shots and committed nine turnovers in the period.
The Bucks ran their lead up to 20 early in the second quarter and were up 58-35 at halftime.
After falling behind by as many as 26 in the third, the Celtics showed a little life in getting the deficit under 15 points in the final minutes of the quarter before Milwaukee rebuilt its advantage to 85-67 after three.
Milwaukee led by as many as 28 points in the fourth.
--Field Level Media
Boston | Milwaukee | |
Al Horford 16 | Scoring | Khris Middleton 23 |
Terry Rozier 9 | Assists | Khris Middleton 7 |
Greg Monroe 12 | Rebounds | Khris Middleton 8 |
Greg Monroe 7 | Free Throws Made | Thon Maker 5 |
Terry Rozier 2 | Steals | Giannis Antetokounmpo 2 |
Jayson Tatum 1 | Blocks | Thon Maker 5 |
Team | Points | FG% | 3PM-3PA | FTM-FTA | Assists | Rebounds | Blocks | Steals | Turnovers |
Boston | 92 | 40.0 | 8-24 | 20-28 | 17 | 45 | 1 | 3 | 18 |
Milwaukee | 116 | 57.0 | 16-33 | 10-15 | 28 | 37 | 12 | 8 | 9 |