Playing to the crowd and energizing his teammates as leading scorer Joe Johnson watched the game with an injured knee, Smith knew his performance was the reason Atlanta held off hard-charging Oklahoma City.
"I'm an emotional guy," he said. "I'm the emotional leader of this basketball team and whenever we can make some defensive stops and put them together, that definitely has to get you fired up."
Smith scored 13 of his 30 points in the fourth quarter, Jeff Teague added 16 points and the Atlanta Hawks snapped the Thunder's seven-game winning streak with a 97-90 victory on Saturday night.
Smith, who matched a season-high in scoring and pulled down seven of his 12 rebounds in the fourth, had dunks on consecutive possessions to give the Hawks an 87-79 lead with 4:43 remaining.
Then, after forcing Durant to commit a turnover and pounding his first against his own chest with 3:04 left, Smith matched Durant's 3-pointer to put Atlanta up 92-88 at the 2-minute mark.
One minute later, Smith drove past Ibaka on the right side and rolled in a left-handed hook to make it 95-90. His efforts helped the Hawks win their second straight.
"I was just real focused," Smith said. "I wanted to be the guy to try to will us to win this game. I was able to find some cracks in their defense and put the ball in the hole."
The Thunder, looking to reach eight straight wins for the first time since February 2010, briefly rallied from their biggest deficit, 11 points on two free throws by Williams at the 2:15 mark of the second quarter, when Cole Aldrich's two free throws put Oklahoma City up 71-70 near the end of the third.
"When they grabbed that lead, we knew we still were in the ballgame," Smith said. "We didn't want to hang our heads and have bad body language. We were able to come out and play a good basketball game tonight."
Durant missed four of his first five shots from the field before faking out Marvin Williams at the top of the key and hitting a 3-pointer that cut the lead to 51-45 in the final seconds of the first half.
The Thunder dropped to 8-2 against the Eastern Conference. Not surprisingly, Oklahoma City, which leads the NBA with an average of 16.9 turnovers, couldn't overcome 21 miscues that led to 22 Atlanta points.
"We've got to fix it," Oklahoma City coach Scott Brooks said. "We keep talking about it. We're working on it. But we've got to figure out that because it's going to be hard to win night in, night out the way we turn it over. We're an attack team. We're an aggressive team. I understand that, but we still have to be solid with our decisions. It's unacceptable having 20 turnovers in an NBA game."
Durant, the MVP of last Sunday's NBA All-Star Game, was just 3 of 10 from the field in the final period, launching missed 3s at the end to try and keep the score close.
"We've won so many games down the stretch, and to lose this one, it's tough, but it's the luck of the draw, man," Durant said. "We've got to move on."
As Johnson missed his second straight game and fifth of the last six with left knee tendinitis, Kirk Hinrich and Zaza Pachulia help fill the offensive void by each scoring 10 points. Pachulia also had 14 rebounds for his fourth double-double of the season.
"The Hawks played hungry tonight even though they were down some guys," Brooks said. "They fought us for four quarters."
Nobody competed harder than Smith, who was coming off a 24-point, 19-rebound effort the night before against Milwaukee.
"We need him to be that impact player, particularly with his energy," Atlanta coach Larry Drew said. "We can feed off his energy. When's playing like that, you can see the rest of the guys step their level of play up."
Westbrook played with a protective sleeve on his left ankle, which he slightly sprained in Thursday's three-point win over Orlando. ... Oklahoma City C Kendrick Perkins had two points and five rebounds in 16 minutes before fouling out with 4:09 remaining. ... A second Thunder starter, G Daequan Cook, did not take a shot and pulled down three rebounds in 14 minutes. ... The Thunder outscored Atlanta 20-4 in fastbreak points. ... The Hawks led points in the paint 42-26. ... Atlanta reserve G Tracy McGrady did not return after playing 1 minute of the first quarter and straining his left knee.