The short-handed Nationals, though, will try to keep gaining ground in the division by winning their second straight over the host Braves on Saturday night.
Washington (28-27) received a scare in its 3-2 victory Friday when Strasburg left after two innings with a strained right oblique. The ace is expected to head back to the nation's capital to have his side examined.
Strasburg has gone 2-1 with a 0.96 ERA in his last four starts.
"We seem to be having all kinds of problems, but we'll get through it,'' manager Davey Johnson said. "Hopefully Stras won't miss too much time.''
Outfielder Bryce Harper was already out of the lineup Friday for the fifth straight game with bursitis in his left knee. Harper, hitting .287 with a team-high 12 homers and 23 RBIs, is unlikely to play in this series.
"We've got to try to figure out whether he needs more rest or what we have to do to get him by that," said Johnson.
Johnson's club could certainly use Harper's bat, as it's hit .239 while dropping eight of 13. The Nationals, however, moved to within 4 1/2 games of the Braves (32-22) with Friday's win.
Washington will send another outstanding pitcher to the mound Saturday, though it hasn't provided much support for Gio Gonzalez (3-3, 3.90 ERA) of late. The left-hander has gotten eight runs while going 0-1 over his last four starts despite a 2.36 ERA.
He yielded four runs and four walks over 5 2-3 innings in his shortest outing since April on Monday, a 6-2 loss to Baltimore.
Gonzalez hasn't pitched well against the Braves, going 2-4 with a 6.75 ERA in six career starts. He's given up 12 runs, eight walks and 14 hits - three homers - over nine innings in two losses to Atlanta this season.
Andrelton Simmons homered off Gonzalez in both of those meetings, and he's 4 for 9 with four RBIs lifetime against him. Simmons has gone 10 for 27 in his last six games overall.
Evan Gattis, 7 for 14 with two homers in his last four contests, is 3 for 5 with two doubles and three RBIs against Gonzalez.
Since winning eight in a row, the Braves have lost four of six. Their scheduled starter for this game is also struggling.
Tim Hudson (4-4, 5.37) has gone 0-3 with an 8.69 ERA in his last four starts. The right-hander, though, is 3-0 with a 2.97 ERA in five starts at home this season.
He's also pitched very well versus Washington, going 2-0 with a 1.29 ERA in two starts in 2013 and 16-5 with a 2.55 ERA in 28 career matchups.
Hudson gave up one run and three hits over seven innings to beat Gonzalez and the Nationals 8-1 in Atlanta on April 30. Gonzalez lasted four innings and allowed five runs with five walks, though he recorded nine of his 12 outs via strikeout.
Freddie Freeman went 3 for 5 with three RBIs in that contest and homered off Strasburg on Friday. He's 11 for 22 with two homers in his last five games.
Washington's Denard Span, who went 3 for 4 with two triples in the series opener, has gone 6 for 8 with four extra-base hits in his last two games at Turner Field.