The social networking site is seeing huge traffic when a big goal is scored in the soccer tournament. Though Twitter normally sees about 750 tweets per second on an average day, there were 2,940 tweets per second, then a record, after Japan scored against Cameroon on Monday.
Nearly as much traffic was reported after Brazil's first goal against North Korea on Monday, as well as after Mexico's tying goal against South Africa on June 11.
Twitter has yet to announce its numbers for Friday's U.S.-Slovenia 2-2 draw, which was likely to have caused huge amounts of activity.
Basketball, though, is still trumping soccer. Thursday night's NBA Championship game between the Los Angeles Lakers and Boston Celtics generated as many as 3,085 tweets per second.
Enormous traffic from the World Cup has contributed to frequent outage problems for Twitter. The site is postponing a planned network overhaul until the World Cup tsunami is over.