It will mark his first start against Atlanta since he was part of a seven-player deal in July 2007.
"He's a great dude. On the field, he was one of the best pitchers I played with in the Minor Leagues," former teammate and current Braves reliever Jonny Venters said. "He really knew what he wanted to do and he was really good at executing his pitches.
"When I played with him, he was maybe 19, 20 years old. But he still had a feel for three good pitches. He was really good. He's still pretty good."
The Texas left-hander enters Saturday's game having lost back-to-back starts. On Sunday against the Twins, Harrison went six innings, giving up two runs on five hits, while walking three and striking out three.
In that game, Harrison got hit by a line drive in the left arm, yet will make Saturday's start on an extra day of rest.
While Harrison is just 5-6 with a 3.31 ERA, he has thrown six or more innings in nine of his 12 starts and has the fifth-lowest road ERA in the American League at just 2.37.
Braves starter Derek Lowe will look to snap a seven-game winless streak. Unlucky during that stretch, Lowe has received six no-decisions in his past eight starts, despite the Braves winning all six of those games. His last victory came May 6.
On Monday against the Astros, Lowe gave up five runs on eight hits in 51/3 innings to take the loss and fall to 3-5 with a 4.02 ERA.
"I wouldn't say [Lowe] didn't have it," Atlanta manager Fredi Gonzalez said after the game. "He gave up 10 ground-ball outs, and I don't even know how many singles went through the hole."
Rangers: Top picks Matthews and Cone sign
Texas announced Friday that it signed its top two picks from this year's First-Year Player Draft.
Pitcher Kevin Matthews, the No. 33 overall pick, agreed to a signing bonus of $936,000, while outfielder Zach Cone, taken 37th in the compensation round, agreed to an $873,000 bonus.
While both players are from Georgia, Matthews will be assigned to the Arizona Rookie League Rangers and Cone will play for Class A Spokane in the short-season Northwest League.
"It was important to get them signed quickly and playing so they could continue their development," said Texas general manager Jon Daniels.
Braves: Hanson heads to disabled list
With inflammation surrounding his right rotator cuff, starter Tommy Hanson was placed on the 15-day disabled list Friday.
Hanson felt relieved when an MRI exam showed no structural damage.
"I just don't want to keep going out there with inflammation in my shoulder and drop my arm slot or something and then mess something else up," Hanson said. "Then instead of being out for a couple starts, I'm out for a year or something."
In addition to placing Hanson on the disabled list, the Braves sent infielder Brandon Hicks back to Triple-A Gwinnett while recalling right-hander Jairo Asencio.
The Rangers are 128-124 all-time in Interleague Play and 46-30 since the start of 2007.
Texas is 7-12 in games decided by one run and 1-11 on the road in those games.