Why did Brentford-Liverpool have a different referee after half-time?

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Liverpool’s Premier League match at Brentford saw a change of referee at half-time after Simon Hooper picked up an injury. The referee was replaced by the fourth official Tim Robinson for the second half at the Brentford Community Stadium.

Brentford led Liverpool 2-1 at the break after an incident-packed first half in west London. Kevin Schade doubled Brentford’s lead on the counter-attack, around a minute after referee Hooper had waved away appeals for a penalty when Cody Gakpo went down under the challenge of Nathan Collins in the box.

Liverpool’s Milos Kerkez then pulled one back in the fifth minute of first-half stoppage time. The Liverpool and Brentford players then emerged onto the pitch before the officials, with Hooper replacing Robinson on the touchline.