LeBlanc picked up his first win since August 25 of last season on Sunday in Cincinnati, as he held the Reds to a three runs and two hits in six innings. He is now 1-2 on the year with a 4.54 ERA.
LeBlanc has faced the Marlins twice and is 0-1 with a 5.84 ERA.
Florida, meanwhile, will rely on lefty Chris Volstad, who was roughed up in his first start back in the majors on Sunday. After a minor league stint Volstad absorbed the loss to the San Francisco Giants, allowing four runs and seven hits in six innings. He also allowed three home runs and dropped to 5-9 on the year to go along with a 5.60 ERA.
Volstad is 2-2 lifetime against the Padres with a 5.49 ERA in four starts.
Stauffer (8-9) bounced back from one of the worst outings of his career by limiting the Marlins to five hits. One of those hits was a home run by John Buck in the seventh.
"I think the use of the changeup kept those guys off balance," Padres manager Bud Black said. "The big difference between this start and last was more balls down in the zone, more balls down and away, he went inside, he hit his spot."
Stauffer lasted just three innings in a loss in Cincinnati on Saturday, as he allowed nine runs and seven hits.
Heath Bell retired the side in order in the ninth for his 33rd save.
Javier Vazquez (7-11) allowed five hits and fanned five over six innings in the opener of this four-game series.
The Marlins lost for the 12th time in 14 games.
"We have a tough time getting our offense going every night," Marlins manager Jack McKeon said. "We've been killed the first inning. We're just going to have to start bearing down a little bit."
The Padres swept a three-game set from the Marlins back in July and have won 10 of their last 13 overall against them.