16.4m Tweets were posted during the Brazil vs. Chile World Cup match

"Last night’s World Cup match against Brazil and Chile broke Twitter records as it became the most tweeted about sports event ever.
The match was ultimately decided on during a penalty shoot-out and Gonzalo Jara’s missed penalty, which handed Brazil the win, generated 389,000 tweets per minute (TPM), eclipsing the record previously set by the Super Bowl where the peak was 382,000 TPM
A record total of 16.4 million tweets were also sent around the game, making it the most-discussed match of the World Cup so far."

Source:  The Drum, 29th June 2014