"Really? I didn't know that," said the rookie before pausing and adding "We're 1-0 against them now. I feel pretty good."
Joe Johnson scored 26 points, including 20 in the second half, and Anthony Johnson had 14 assists to help the Hawks end their nine-game losing streak against Utah, holding off the Jazz 116-111 on Monday night.
Carlos Boozer scored a season-high 39 points with 12 rebounds and was the major reason six Atlanta players finished with four or more fouls.
The teams combined for 92 free throws, including 50 by Atlanta. Utah, which had its sixth straight road loss, made only 29 of 42 free throws (69 percent) while the Hawks shot 57.6 percent from the field.
"We were out there trying to stop 57 percent shooting, and if you have to play against that, it's difficult to win," said Utah coach Jerry Sloan.
"If we'd still been playing and made our free throws, you always have a chance. It would have made it a little bit closer there at the end. You never know what would have happened."
The Hawks built a fourth-quarter lead and didn't falter when Utah staged its inevitable challenge.
A jam by Horford gave the Hawks a 110-100 lead with 2:09 left.
Deron Williams, who had 14 points and 10 assists, made two of three free throws with 17 seconds left to cut the lead to 113-108.
Zaza Pachulia made one of two free throws for a 115-111 lead with 3 seconds left.
Anthony Johnson had 17 points with his season-high total for assists and made two 3-pointers in the fourth quarter.
"He was our engine, our motor," Smith said.
"We needed to find offense somewhere, and A.J. gave it to us."
Boozer also said Anthony Johnson was the difference.
"We had a couple great steals and some great plays, but not enough," Boozer said. "Anthony Johnson probably played the best game of his career tonight."
"I know what I'm capable of, given the opportunity," said Anthony Johnson, who gave credit to Joe Johnson.
"He did a great job of carrying us down the stretch."
Joe Johnson said the final 2 minutes "were definitely scary. I was praying they wouldn't come down and shoot a 3-pointer."
Utah, which lost to Atlanta for the first time since Oct. 31, 2002, fell to 5-10 on the road this season.
Horford also had 17 as every Atlanta starter scored at least 17 points.
Boozer fouled out with 2 seconds left to finish two points shy of matching his career high of 41 points set against Washington last March. Andrei Kirilenko scored 16 points for Utah.
The Hawks (12-12) moved to .500 for the third time this season.
Utah, which ended a six-game losing streak with a win over Seattle on Saturday, has lost seven of eight.
"You've got to play a perfect finish the way we've been playing," Sloan said. "This was not even close to that.
"We've got to do something where we help each other."
Fouls were a concern for the Hawks. Smith, Pachulia and Mario West entered the fourth quarter with four fouls.
Smith left the game with his fifth foul with 8:14 left. Horford, who had to guard Boozer most of the night, was assessed his fifth with 4:12 left.
Utah appeared to be on the verge of putting the game away in the third quarter.
Hawks coach Mike Woodson called a timeout after a basket by Boozer gave Utah a 66-57 lead, but the Hawks came out of the timeout with a 10-0 run to regain the lead.
How long ago was that last win over the Jazz for Atlanta? Glenn Robinson, how a distant memory for Hawks fans, led Atlanta with 20 points in the win.
Smith had four fouls in the third quarter. ... Hawks C Lorenzen Wright missed the game with flu-like symptoms. Josh Childress (strained groin) missed his third straight game. ... Utah F Matt Harpring, is expected to meet the team for its game in Charlotte on Wednesday, pending the outcome of tests for gastric distress. ... Miles had 10 points off Utah's bench.