Smoltz won his sixth straight home start Saturday, giving up only three hits in eight innings in the Braves' 10-1 victory over Washington.
Of the Braves' 11 home wins since July 3, six belong to Smoltz.
The Braves are only 27-34 at Turner Field for the second-worst home record, only slightly better than the Cubs' 27-36 mark.
Smoltz, 8-1 in July and August with an Aug. 16 loss at Washington, has served as the stopper as each of his last five wins have followed losses.
"I've prided myself my whole career on that," Smoltz said. "Right now we need it more than ever. I'm just trying to go undefeated the second half. I lost that one game in Washington, but I want to start another streak. So far so good."
Braves manager Bobby Cox, who has seen each of Smoltz's 189 career wins, says his ace, at 39, is in top form.
Smoltz (12-6) is a combined 26-13 in two seasons back in the starting rotation after recording 154 saves from 2001-04.
"He's as good as I've ever seen him, and he's been that way all year," Cox said. "His control is just devastating and his stuff is just devastating."
Smoltz struck out seven and did not walk a batter in lowering his ERA to 3.36. He is second in the league with 176 strikeouts.
Smoltz retired the first 13 Washington hitters before giving up a fifth-inning triple to Austin Kearns. But Kearns was stranded on third as Smoltz struck out the side.
"He was throwing four pitches for strikes," said Washington's Ryan Zimmerman. "He was getting ahead and you had to guard against four pitches. That's hard to do with him throwing 95 miles per hour."
Cox said Smoltz felt so good he asked for permission to steal second base after his second-inning single. Cox did not give the go-ahead.
Bob Wickman pitched the ninth, finishing the combined four-hitter.
Less than two weeks after recording his 12th career shutout in a 5-0 win over the Braves on Aug. 15, Pedro Astacio (3-4) couldn't come close to matching that form.
Instead, for the second straight start, Astacio was chased in the third inning. After giving up seven runs in a 12-10 loss at Philadelphia on Sunday, Astacio gave up six runs on eight hits and five walks in 2 2/3 innings.
"It's crippling," said Washington manager Frank Robinson. "It just tears your bullpen up.
"Smoltz is tough enough as it is. When you give him that type of cushion, it's really rough."
"I was pitching behind," Astacio said. "It got some over the middle of the plate. When you make a mistake, they don't miss it."
The Braves added two runs in the third on a balk by Astacio and Giles' RBI single. Langerhans' sharp grounder skipped past first baseman Nick Johnson for a two-base error in the fifth and Giles' double pushed the lead to 7-0.
Jones hit a two-run homer in the eighth.
- Trainers came out to check Francoeur and Johnson after the two collided in the sixth inning. Johnson, running for Francoeur's pop foul, ran into Francoeur in the basepath. Francoeur was called out for interference as both fell to the grass. Johnson was replaced by Anderson the following inning. Johnson is day to day with a cervical strain. Francoeur stayed in the game one inning before leaving with sore ribs and a sore shoulder.
- Smoltz's first three-ball count came with one out in the eighth, against Robert Fick. Smoltz struck him out.