With Sunday, July 18, the third and final day of the 2010 Pitchfork Music Festival officially sold out, promoters Jam Productions have announced that the big draw in Union Park that day—reunited ’90s alternative-rock heroes Pavement—will return to Chicago for an encore performance at the Pritzker Pavilion in Millennium Park n September 13.

No Age will open the show at 7 p.m., and tickets go on sale Saturday (June 19) at 11 a.m., with reserved seats priced at $40 and lawn seats at $15‚  (plus egregious Ticketmaster service fees, of course).