Sosa allowed only two runs and five hits in five innings in his first start of the season after 21 relief appearances to help the Braves beat the Texas Rangers 7-2 on Tuesday night.
Rookie Kelly Johnson hit his first major-league homer and 46-year-old Julio Franco also connected in a five-run fifth to back Sosa (3-0), pressed into the rotation with starters John Thomson and Mike Hampton sidelined by injuries.
"Sosa did a great job when we really needed somebody," manager Bobby Cox said. "He didn't walk anybody and that is the key in a spot start."
Cox had said before the game that Sosa, who struck out seven and didn't allow a walk, wasn't going to go more than five innings, and Cox was true to his word. Sosa, who had made 41 starts for Tampa Bay, hadn't gone more than 2 1/3 innings this season.
"It was my first start in a while so it's hard to go five," Sosa said through his interpreter, third base coach Fredi Gonzalez. "I feel good that the Braves had the confidence in me to start again."
Mark Teixeira hit his 17th homer for the Rangers, who had their nine-game home winning streak snapped.
The Rangers took a 2-1 lead into the fifth. Starter Pedro Astacio had retired 13 of his previous 14 batters when he hit Ryan Langerhans with a pitch. Wilson Betemit followed with a single and Johnson, batting .059 and in a 2-for-34 slide entering Tuesday, put the Braves in front 4-2 when he homered to right-center.
"A lot of factors make this really sweet," said Johnson, who lives in Austin and had a large group of supporters in the stands. "Obviously winning the game. It's a day I can look back on and remember. To be in your home state and have a lot of family and
friends in town was great. It's a good day to build on."
Marcus Giles singled later in the inning and Franco hit his third homer to make it 6-2 and knock out Astacio (2-8).
Earlier in the sequence, Franco lost the grip on his bat, which went sailing into the stands, grazing a young fan. Franco gave the boy another bat in exchange, and Franco used the original bat for the homer.
"I'm very picky about my bats," Franco said. "Out of 12 you order, seven or eight are good bats. When you get a good bat, you want to keep it. I'd rather give him a bat I'm not using at the time."
Johnson had three hits and drove in three runs. Franco, who played for the Rangers from 1989-93 and won the AL batting title in 1991, also had three hits and three RBI.
Astacio, whose rotation spot could be in jeopardy after a series of shaky starts, allowed six runs and seven hits in 4 1/3 innings. He struck out three and didn't walk a batter.
"Sometimes when you don't do your job, the job can be on the line," said Astacio, who has lost seven of his last eight decisions. "I have to go out every time I have the ball and do the job. If you don't, you're not going to be there."
Johnson led off the game with a double, his first major-league extra-base hit. He moved to third on a sacrifice bunt and scored on Franco's single.
The Rangers came back in the first when Michael Young singled and Teixeira put the Rangers in front when his homer broke an 0-for-15 slump.
Atlanta padded its lead to 7-2 in the sixth on Andy Marte's RBI single.
Atlanta is 7-1 overall against Texas. ... Young has hit safely in 22 of his last 23 games. ... Sosa did not allow a walk for the first time in 42 career starts. ... Astacio has allowed at least one homer in nine straight starts. ... Texas' Alfonso Soriano had his 15-game hitting streak snapped, striking out three times. ... Rangers DH David Dellucci, who started the night with an AL-leading 45 walks, had four strikeouts.