Liverpool stormed into a two-goal lead in the first half of their Premier League clash with Huddersfield.
Naby Keita and Sadio Mane were the duo who caught the eye, but one moment from the first 45 minutes at Anfield caught the ears of Sky Sports viewers when an announcement was made over the stadium loudspeaker.
The announcement stated that "Operation Anfield Exercise has been completed.
Social media users immediately took to Twitter to ask the same question, after the announcement - which was ignored by both players and match officials - was made to try and discover what it was all about.
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So what does the announcement mean?
Operation Anfield Exercise is simply an exercise for the stewards, who are required to prepare for an emergency at a moment's notice.
The announcement acts as a command for the stewards to get into their correct positions.
Meanwhile turnstiles are tested to make sure they work to ensure fans can leave the ground as quickly and as safely as possible, should they need to.
The announcement is made at most home games each season as a drill.
