Chris Billam Smith added the European and British cruiserweight titles to the Commonwealth belt he already held with a split decision victory on Matchroom Boxing's first instalment of Fight Camp 2021.
The 30-year-old Smith, known as 'The Gentleman' looked like the winner at the end of the 12 rounds but McCarthy did enough to close the gap in the last third of the contest to deserve an immediate rematch.
Scores: Ian John-Lewis 116-112 | John Latham 114-115 | Mark Lyson 115-114.