The Chargers have until 1:15 p.m. Friday to sell the remaining 1,100 tickets.
Both of San Diego's exhibition games were blacked out locally.
The NFL requires games to be sold out 72 hours before kickoff to be aired on local TV.
Jim Steeg, the Chargers' Chief Operating Officer said the team is doing what it can to sell more tickets.
"We've made our payment terms more flexible. We initiated our individual game sale earlier than in the past," Steeg said.
The organization is also sending email blasts and trying to attract fans from Orange County and Los Angeles.