However, after that promising start, Sanchez finished his Marlins career just 39-38 and was traded to the Detroit Tigers on July 23, 2012.
On Saturday, Sanchez will pitch at Marlins Park for the first time since April 6, 2016. In that game, he outdueled the late Jose Fernandez in a 7-3 Tigers win.
This time, Sanchez (6-4, 3.13 ERA) will pitch for the Atlanta Braves against Marlins left-hander Wei-Yin Chen (4-9, 5.20 ERA).
Sanchez is 34 now, and he is enjoying a resurgent season after posting successively worse ERAs in each of his past three seasons: 4.99, 5.87 and 6.41.
This year, Sanchez has allowed three earned runs or less in 13 of his 17 starts. And his homer rate is down from 2.2 per nine innings last year to 1.2 this season.
The Venezuela native's average fastball is 90.4 mph at this point in his long career. The league average is 93.1.
One caution about Sanchez is that he was 4-2 with a 2.60 ERA in 12 first-half games but has struggled a bit since. He is 2-2 with a 4.22 ERA in six second-half starts.
Sanchez has faced the Marlins once this year, and the Braves won that game 10-6 at home. Sanchez allowed five runs (four earned) in five innings.
Braves rookie left fielder Ronald Acuna homered twice in that game. On that night, at age 20, he became the youngest major leaguer to hit a home run in five straight games.
"It's contagious what he's doing," Braves center fielder Ender Inciarte said about Acuna.
On Saturday, Sanchez will face Chen, who has had one of the most unusual seasons in the majors. Chen is 1-6 with a 9.35 ERA on the road but 3-3 with a 2.05 ERA at home.
Chen, whose average fastball is just 91.1 mph, is 1-1 with a 2.08 ERA in three starts this month. But he had a 7.01 ERA in May, a 6.20 ERA in June and a 5.27 ERA in July.
He beat the Braves on July 24 at Marlins Park, allowing three runs in six innings.
The Marlins also beat the Braves 1-0 on Friday night, tying the four-game series at one apiece.
If the Marlins have to go to the bullpen on Saturday, they won't have Jarlin Garcia, who was placed on the disabled list Friday because of a contusion on his right leg.
Taking his roster spot is former closer Kyle Barraclough, who had been on the DL because of back stiffness.
"We want (Barraclough) to work his way back up," Marlins manager Don Mattingly said.
Barraclough received National League Reliever of the Month honors in June after allowing just one hit and no runs in 12 innings, converting all seven of his save chances.
But Barraclough blew a save chance on July 2, and that started his downfall. In July, he posted a bloated 8.38 ERA in 9 2/3 innings, blowing three of five save chances.