Major League Soccer on Tuesday announced an "elevated" security policy for fans entering games.
Upon entry to stadiums, the league will now subject all fans to full screening "via a full pat down or with the use of a search wand of magnetometers."
The new policy also greatly limits bags that fans are allowed to bring into games.
MLS said the new standards will bring "MLS events in line with security measures taken by the other professional sports leagues in North America."
Increased security is likely to cause longer delays entering stadiums, and the Philadelphia Union advised fans to "arrive early.