was a Czech football goalkeeper and one of the most honoured players in the history of Czechoslovak football. He played all his career for Slavia Prague, during which time the club won the Czech league eight times and the Mitropa Cup once. He also became a member of the Czechoslovakia national team, where his first success as a young goalkeeper was helping Czechoslovakia to become runner-up in the Central European International Cup 1931–32 and later became captain during the World Cup finals of 1934 (where the Czechoslovakia team finished second) and 1938.

Plánička was a courageous player, to the extent that in Czechoslovakia's 1938 World Cup match against Brazil, he remained on the field despite having suffered a serious injury. This injury ended a career that saw him play a total of 1253 matches, in which he conceded only 1073 goals, an average of 0.86 goals per game. He was a goalkeeper of outstanding reflexes and shot-stopping abilities and was also characterized by his sportsmanship, never once being cautioned or sent off in his 20-year career. He was awarded the UNESCO International Fair Play Award in 1985.

Regarded as one of the greatest goalkeepers of his generation, and of all time, in 1999, the IFFHS elected him the best Czech goalkeeper – as well as the sixth best in Europe and the ninth best overall – of the twentieth century. In 2003, he was cataloged as the greatest pre-war goalkeeper in Europe along with other notable keepers such as Ricardo Zamora and Gianpiero Combi.