Gabriel Trifu played tennis as a professional from 1994 to 2005 before being made the captain of the Romanian Davis Cup team in 2017. Trifu achieved a career-best singles ranking of #148 in the world in April 2002 and a doubles ranking of #97 in the world in July 2005. From 1997 to 2005 he won 13 doubles titles on the ATP Challenger and ITF Futures Circuit, along with one singles title in 1999. He only won one ATP title when he and compatriot Andrei Pavel were victorious at the 1998 Romanian Open. Two years later, Trifu and Pavel competed together in the doubles at the 2000 Sydney Olympics, but lost in the first round to Mahesh Bhupathi and Leander Paes of India.