Lozano played from 1983 to 1985 for the University of Southern California and in 1986 became a professional tennis player. In the same year he stood at the side of Todd Witsken, his partner from college times, in the quarterfinals of Indianapolis. In 1987, he reached his first doubles final at the ATP World Tour in Itaparica with Diego Pérez. The following year he was able to win with Todd Witsken four tournament wins, two more followed in 1989. After two final defeats in 1990 parted ways from Lozano and Witsken, Lozano won then with other partners double three other tournaments. Overall, he was able to win nine titles in the doubles competition, six of them with his longtime partner Witsken. A further 13 times he stood in a double finals. Its highest listing in the tennis world ranking he reached in 1988 with position 51 in singles and fourth position in the doubles.
His best individual result at a Grand Slam tournament was reaching the second round of the U.S. Open 1988. During the same year he stood there on the side of Todd Witsken also in the semifinals of the doubles competition. Both also reached this year the quarterfinals of the French Open. In 1988 he won at the side of Lori McNeil Mixed competition of the French Open. In 1990, he repeated this triumph with Arantxa Sánchez Vicario.
Lozano played 1982-1995 19 singles and 24 doubles matches for the Mexican Davis Cup team. In his first inaugural in 1981 was the opponent in the Erstrundenbegegnung the World Group USA. Although he won the doubles at the side of Raul Ramirez, but lost in both Isolated against John McEnroe and Roscoe Tanner. In 1986, he was employed in the quarter-final match against the USA in the doubles with Fernando Perez -Pascal, he was defeated by world-class Ken Flach and Robert Seguso double in four sets.
Lozano since 2009, team boss of the Mexican Davis Cup team.