[3] On 3 February 2018, KSI fought fellow YouTuber Joe Weller at the Copper Box Arena in London, defeating him via technical knockout in the 3rd round.

[6] On 9 November 2019, a professional rematch was held at the Staples Center in Los Angeles in which KSI defeated Logan Paul via split decision.

However on 23 March, Prime Minister Boris Johnson announced the first national lockdown in the United Kingdom in response to the COVID-19 pandemic which prevented KSI from being able to train for the bout.

On 8 August however, KSI tweeted an offer to Paul stating that they will fight in 2023 at Wembley Stadium with the winner taking 100% of the purse made from the event.

[17] On 14 January 2023, KSI fought and defeated Brazilian YouTuber FaZe Temperrr via knockout in the 1st round and immediately called out Paul.

[20] On 13 May, KSI fought professional boxer Joe Fournier and originally won via a controversial knockout in the 2nd round, but was later overruled to a no contest due to an unintentional elbow strike.

Paul fought and defeated professional boxer Andre August via knockout in the 1st round while KSI and fellow YouTuber IShowSpeed held a charity spar for the Anthony Walker Foundation at the exact same time.

[‡ 3] On 8 June, KSI uploaded a YouTube video proposing one final offer to Paul for May 2025 at 185 Ibs with the option to have the bout take place in the US rather than England.