Ersson exited Thursday's game against Vancouver early in the third period due to dehydration, Elliotte Friedman of Sportsnet reports.
Ersson saved 18 of 19 shots in 42:36 of ice time before having to leave the contest. Carter Hart drew into the game as a result. Hart will probably play in Friday's road game against Seattle, but the Flyers will need to recall a netminder from the minors if Ersson isn't available for that game.