Three months later he faced Canadian Arthur King for the vacant British Empire title in Manchester, but Thompson retired at the end of the seventh round with a cut above his eye impairing his vision.
In July he made a fourth defence of the European title against Kid Dussart, losing it after being disqualified in the sixth round for hitting low after being warned three times.
[12] After adopting a meat-free diet to get down the lightweight limit, he successfully defended his British title for a second time in July against Tommy McGovern, winning the Lonsdale Belt outright.
[4][13][14] He made a second attempt to regain the European title in February 1951 when he met Montane again after Proietti vacated, but was knocked out by the Frenchman in the twelfth round.
[15] In August 1951 he faced McGovern at Wandsworth Stadium to try to regain his British title, but was knocked out after 45 seconds of the first round, after a struggle to make the weight that had reportedly led him to spending four hours in a Turkish bath the night before the fight had left him weakened.