Keuchel last pitched Thursday in Game 1, meaning he will work on just three days’ rest Monday in St. Louis.
“He’s ready,” Braves manager Brian Snitker said. “I mean, he’s good to go. He’s gassed up.”
The former Cy Young Award winner threw just 74 pitches in the series opener, but Monday’s contest will mark just the third time in his career that he’ll start on short rest.
Snitker had indicated Sunday night that Keuchel was an option to start Game 4 but said he would wait until Monday to make his final decision.
With an off-day Tuesday, Snitker also noted that nearly all of Atlanta’s pitchers will be available in Game 4. The only pitchers who likely will not be available is Game 3 starter Mike Soroka.
Mike Foltynewicz, who is expected to start Game 5 in Atlanta if necessary, is “available,” Snitker said, “if something happened, you know? “
The Braves took a 2-1 series lead Sunday with a 3-1 victory in Game 3, highlighted by a dramatic three-run ninth-inning rally.
Keuchel, 31, pitched 4⅔ innings and did not record a decision in Atlanta’s Game 1 loss, allowing one run and five hits with three walks and no strikeouts.
The two-time All-Star is 4-2 with a 3.20 ERA in 11 career postseason games, including 10 starts.
ESPN’s Jesse Rogers contributed to this report.