Johnson scored 14 of his season-high 28 points in the fourth quarter to lead the Hawks over the Milwaukee Bucks 97-92 on Monday night.
Trailing by four to start the fourth, the Bucks chipped away and caught the Hawks on a 3-pointer by Brandon Jennings, a free throw by Ersan Ilyasova and two from Mike Dunleavy that gave Milwaukee a 74-73 lead with 8:21 left.
"When they took the lead in the fourth quarter, it was a chance for us to see what we were made of," Hawks coach Larry Drew said of the Bucks' last gasp. "Our guys preserved."
The Hawks never let the lead get past four before Johnson led them back.
"I was just trying to pick my spots," he said. "It was a tough first three quarters for me. In the fourth, I didn't want to stop being aggressive and I wanted to take what the defense gave me."
His long jumper tied it at 84, and then his next two shots from in close pushed the lead to three. Drew Gooden hit a 3-pointer from deep in the corner, but Josh Smith answered with a 3 that gave Atlanta the lead for good.
Drew said he knew he could depend on Johnson to get the job done.
"He has been money," he said. "He's a guy we rely on a lot [particularly] in those situations. He was really in a rhythm."
Johnson scored just four points in the first on 2-of-9 shooting. In the third, he started to find his stride, scoring 10 points.
"One thing I wanted to do in the second half was to get him into a rhythm," Drew said. "I had my mind made up I was going to leave him out there until he got into a good rhythm. He did that, and he came up with some big shots."
Smith's 3 with less than a minute to go was a pretty big shot, too.
The Hawks whipped the pass around the 3-point arc before it found Smith, who calmly hit the shot.
Bucks coach Scott Skiles said his team didn't cover real well on that play.
"We broke down a little bit, but Joe puts the pressure on you," he said. "He collapses the defense, and he can see people. He made a nice pass out. [Jeff] Teague made a nice play, and Josh knocked it down."
Johnson, who came in averaging 18.6 points, was 10-of-22 from the floor and 8-for-8 from the line. He had five rebounds and two steals. Smith had 19 points and 13 rebounds, and Teague added 15 points for Atlanta.
Smith was impressed with Johnson.
"This is the first game where I have seen him in a long time where they were just beating on him all night," Smith said. "He just showed so much resilience. He didn't stop playing. I was just glad to see our leader lead like that."
With the Bucks on the attack for the last time, Marvin Williams deflected a pass from Dunleavy and the Hawks came up with the loose ball. Milwaukee fouled Smith with 9.7 seconds left. He made the two free throws, and after Jennings raced in for a driving layup for Milwaukee's final points, Johnson made two free throws for the final margin.
Jennings had 21 points and 11 assists to lead Milwaukee, and Dunleavy added a season-high 17 points.
Andrew Bogut had six points and 12 rebounds, and Gooden added 13 points for Milwaukee, which hoped to build on the momentum of big victories on the road.
The Bucks, who started 0-8 away from home, won 100-86 at New York on Friday and then 91-82 at Miami on Sunday despite shooting 35 percent.
Trailing 70-64 after three quarters, the Bucks opened the fourth with a 10-3 surge.
Dunleavy started it with an 8-foot jumper and capped it with two free throws that gave Milwaukee the lead at 74-73 with 8:21 left. It was the 18th lead change in the game.
The Bucks recovered from shooting 9 of 23 (39 percent) in the first quarter with an 11 of 22 effort (55 percent) in the second to tie the score at 48 as the half ended.
Teague scored 11 points on 5-of-7 shooting for Atlanta, which shot 54.5 percent in the first quarter.
Hawks G Kirk Hinrich has missed 17 games (left shoulder surgery) but made the trip. He has been practicing hard, according to coach Larry Drew, and might return to action during the road trip. ... Oak Hill Academy (VA) was well represented at the game. Atlanta's Josh Smith and Jerry Stackhouse and Milwaukee's Brandon Jennings and Stephen Jackson all graduated from there. ... Milwaukee Brewers general manager Doug Melvin and his wife, Ellen, were in attendance.