Drobac was born in 1927 in Milwaukee. He met Frank Beeman, a future MSU tennis coach, while serving in the U.S. Army in Europe after World War II, according to the release. When Drobac came home, he participated in major tennis tournaments, including Wimbledon, where he played doubles with Beeman, according to the release. He completed bachelor's and master's degrees from MSU in 1953 and 1956, respectively, with brief stints as East Lansing High School tennis coach and as an MSU physical education instructor in between, the release said.

During Drobac's years as a Spartan tennis player, he won two Big Ten doubles championships with partner Tom Belton, as well as one conference singles championship and one runner-up finish. When the MSU men's tennis All-Century Team was announced in 2013, Drobac was named its Most Valuable Player.

In 1958, Drobac became men's tennis coach at MSU. He was an immediate success, achieving 10 winning seasons in a row from 1959-1968. The 1967 season was one of the highlights of Drobac's coaching career. That year, he led the Spartans to a 15-4 record, including 9-0 in conference play, and won the Big Ten championship, the release said.

Drobac's various tennis innovations include inventing a new tennis scoreboard and scorebook, founding the precursor to the NCAA team tennis champions, and helping develop MSU's wheelchair tennis program, the release said.

Drobac was also a member of the first NCAA Tennis Committee and served as president of the Intercollegiate Tennis Coaches Association for four years.

Drobac's visitation will be held at Fountain Inn Memorial Church Monday from 4-6 p.m. The funeral services will be held in East Lansing at a date and time yet to be determined.

In lieu of flowers, memorials can be made to the MSU men’s tennis program by selecting the “Tennis – Men’s” category.