Dave was a power-hitting first baseman and third baseman who was drafted by the Montreal Expos in 1984. That year, he played for the Calgary Expos in the Pioneer League, where he received the Top Hitter Award with a .310 batting average and led the league with a .990 fielding percentage.

In 1985, Dave moved to the farm system of the St. Louis Cardinals, which began with a stint  with the Savannah Cardinals in the South Atlantic League. In 1986, he was presented with an Inspiration Award while playing for the Springfield Cardinals in the Midwest League. 

Pregon also played for Georgia Southern University from 1982 to 1984. During those three seasons, he hit 50 home runs, and his teammate, Ben Abner, hit 59 home runs. Together, they established the NCAA record for most home runs by two players on the same team. Pregon is ranked fourth in career home runs at Georgia Southern and he is ranked sixth in career RBIs and was named All-Conference in 1982 and 1984. He was selected to the all-tournament team in 1982. Pregon ranks 10th on the NCAA list of all-time most prolific home run hitters. In 1984, he received the Georgia Southern Senior Award.

In 1980 and 1981, Dave played for the very successful Meramec Community College team. In 1981, he was the team leader in home runs, runs scored, and total bases. His .366 batting average ranked second on the team.

During the summer of 1980, he played in the St. Louis Metro Collegiate League. During the summer of 1981, he was a first baseman for the Winchester Royals in the prestigious Valley League in Virginia. In 1982, Pregon played for the St. Louis Sotolar Pointers in the CYC Senior Major League.

He was a first baseman and third baseman for Vianney High School in the late 1970s.

Pregon was the Director and Coach of one of the top Travel Baseball Programs in the Midwest, working with thousands of young people. He took his baseball teams to compete in several foreign countries. Several of his players made the USA National team. He conducted baseball camps and clinics.

Pregon coached amateur baseball teams in the St. Louis area for over 25 years.