Nečas became the most expensive player in the history of Czech football in 1992 when Slavia Prague signed him from Baník Ostrava for 25 million Czechoslovak koruna.

[1] One of the highlights of Nečas' time at Ostrava was scoring from a free kick at Bazaly in the first round of the 1990–91 UEFA Cup against Aston Villa.

[1] Nečas became the most expensive player in the history of Czech football in 1992, when he left Ostrava for Slavia Prague for a fee of 25 million Czechoslovak koruna.

[6] He played for Bratislava for two years before returning to the Czech Republic in 2003, where he signed for Bohemian Football League team Chrudim.

[3] Nečas started playing for the national youth teams of Czechoslovakia in 1984, making a combined total of 47 appearances over four years at age groups from under-15 to under-18.

[13] At the beginning of the 2010–11 season he went back to the Czech Republic and joined another Bohemian Football League club, Arsenal Česká Lípa.