Additionally, outfielder Travis Snider was recalled from his rehab assignment and activated off the DL, where he had gone July 28 with chronic discomfort in his left big toe. In 10 games between Double-A Altoona and Indianapolis, Snider batted .342 (13-for-38) with a double his only extra-base hit.
Johnson was picked for the important assignment over other limited options "because of his experience and the ability to move the ball east-west," according to manager Clint Hurdle.
The 28-year-old former first-round Draft pick (2006, Red Sox) has experienced only one big league game -- a six-inning relief stint for the Bucs on Aug. 18 -- but his treads include 169 Minor League starts and has also pitched big games in ultra-competitive winter ball.
"He's pitched a lot of games in front of 20,000-30,000 people. He hasn't pitched a game of this magnitude," Hurdle said. "but with his mound presence, we felt he was best suited to handle this challenge."
Farnsworth got into a half-dozen games at Triple-A (seven hits and three runs in 6 2/3 innings) after signing with the Bucs on Aug. 16. He'd been released by Tampa Bay after 39 relief appearances for the Rays.
"We like the experience," Hurdle said of Farnsworth, "and the intense desire to find his way back."
Tom Singer is a reporter for MLB.com and writes an MLBlog Change for a Nickel. He can also be found on Twitter @Tom_Singer. This story was not subject to the approval of Major League Baseball or its clubs.