Kershaw was scratched from his scheduled start Tuesday against the Braves in Game 2 of the NLCS due to back spasms, Eric Stephen of SBNation.com reports.
The initial diagnosis doesn't appear to be too serious, so it's entirely possible he's able to start one of the next few games of the series. Missing Game 2 essentially rules out any chances of him starting two games in the series, however. Tony Gonsolin will take the hill in his absence Tuesday.