ESPN, which is owned by Walt Disney Co, has been setting U.S. viewing records during the World Cup in Brazil where some games have aired during the U.S. prime time.
Sunday's match became the highest-rated soccer match ever in the United States, edging out the 1999's Women's World Cup final of USA vs. China, where 18 million people tuned in to watch on Disney's broadcast network ABC.
The Sunday match surpassed the U.S.-Ghana game last Monday, which pulled in 11 million viewers.
The game also attracted 6.5 million viewers for Spanish language broadcaster Univision, making it the most viewed U.S. World Cup match in the network's history, and beating last Monday's U.S.-Ghana game which garnered 4.8 million viewers.
On Sunday, the U.S. team had nearly secured a come-from-behind victory with goals from Jermaine Jones and Clint Dempsey, until Portugal substitute Silvestre Varela scored with a flying header from a Cristiano Ronaldo cross. [ID: nL6N0P400P]
The next match for the United States vs. Germany will air Thursday at 11:30 am Eastern on ESPN.
While soccer is on the upswing in the United States, it still lacks the television audience numbers of some other sports. The 18.2 million viewers for the U.S.-Portugal World Cup game on Sunday compares with 26.6 million ESPN viewers for college football's BCS National Championship on Jan. 6.