Drew Smyly didn't allow a hit until the sixth inning, Ronald Acuna Jr. hit his 100th career homer and Atlanta earned a split of a day-night doubleheader with a 1-0 victory over the Cardinals on Sunday night.

Smyly  held the Cardinals hitless until Paul Goldschmidt reached on an infield single with two outs in the sixth. Second baseman Ozzie Albies fielded the ball in shallow right field and made a wide throw to first.

Closer Will Smith pitched the seventh of the shortened doubleheader under pandemic rules, earning his 13th save in 14 chances.

Acuna, playing in his 378th game, became the sixth-quickest to reach the milestone with a shot to left-center in the third inning off Kwang Hyun Kim (1-5). It was his 19th homer, second-most in the NL.

Before the sixth, Smyly allowed three baserunners - a walk of Tyler O'Neill in the second, Goldschmidt in the fourth and O'Neill again in the fourth. Luke Jackson, who entered the game with a 1.05 ERA, struck out O'Neill to end the sixth with runners on first and second.

Acuna hit his first homer in 10 games, snapping his longest drought of the season.

Kim allowed three hits and one run in four innings.

The Cardinals have dropped 14 of 20 after losing the second game.