Atlanta, which dropped seven games behind Pittsburgh in the NL wild-card race, can be eliminated with any combination of three Pirates wins or Braves losses.
The Mets were knocked out when Pittsburgh beat Milwaukee earlier Friday.
The Braves, losers in six of seven, dropped to 4-12 this month. They won the NL East last year, but were eliminated from the division race on Tuesday when Washington celebrated at Turner Field.
Wheeler (11-10) allowed five hits and two walks with seven strikeouts. The Georgia native improved to 6-1 with a 1.92 ERA in 13 road starts, dating to May 29.