At the end of 1953, Gregory was invited to his first international sports car race - the 1954 1000 km Buenos Aires in Argentina, which he finished in 14th due to water pump problems.
A finais de 1953, Gregory foi invitado á súa primeira carreira deportiva internacional: os 1000 km de Bos Aires en Arxentina, no que terminou 14º por problemas de auga.