FIFA insists the attendance figure for the World Cup clash between South Korea and Czech Republic was accurate after pictures appeared to show thousands of empty seats.
The crowd for the Group A fixture at the stadium outside Mexico's Guadalajara on Thursday was announced as a near-capacity 44,985, leading onlookers to question the figure.
However, world governing body FIFA said the attendance was based on "verified operational data" and included all those present within the "stadium footprint".
A FIFA spokesperson added on Friday: "Official attendance figures reflect the number of tickets scanned and spectators present within the stadium footprint, rather than visual assessments of seating occupancy at any given moment during the match.
"FIFA works closely with stadium authorities and ticketing teams to ensure all published figures are based on verified operational data.
"Please note that, during (Thursday's) match in Guadalajara, several ticketed fans could be seen standing in concourses rather than staying in their assigned seats throughout the match."
