West Ham defender Kurt Zouma admitted kicking and slapping his pet cat as he appeared at a court in London on Tuesday, in a case that caused public outrage across Britain.
The France international pleaded guilty to two counts under the Animal Welfare Act at Thames Magistrates' Court in east London.
Zouma, 27, was forced to apologise after harrowing footage was filmed and shared by his younger brother Yoan, 24, who admitted one offence during the hearing.
Hammers defender Zouma arrived at court in chaotic fashion, accompanied by several security guards who emerged from a vehicle holding umbrellas to form a protective shield around the defendant.
The brothers' addresses have been withheld following a court order.
The court was told about disturbing footage of the incident, filmed at Zouma's home and posted on Snapchat by his brother on February 6.
It was later seen by a woman who had been messaging Yoan, who raised the alarm.
Zouma could be seen kicking the Bengal cat across his kitchen, before throwing a pair of shoes at it and slapping its head.
Prosecutor Hazel Stevens told the court Kurt Zouma could be heard saying: "I swear I'll kill it, I swear I'll kill it."
He admitted two counts of causing unnecessary suffering to a protected animal on February 6.
Yoan admitted one count of aiding, abetting, counselling or procuring his older brother to commit an offence.