The first Philippine stamps to feature a sports topical was the set of three issued in 1934 for the 10th Far Eastern Championship Games.
For the 2c value, baseball is shown. This, also, is the first Philippine "baseball on stamp" and the first "baseball on stamp" in the world (beating that of the United States issue which came out for the centennial of baseball in 1939).
The 6c value features a tennis player. This is the first Philippine "tennis on stamp". Look at the outfit!
And the 16c value shows two basketball players (to me they look more like volleyball players!) and this is the first Philippine "basketball on stamps" as well as reportedly the first "basketball on stamps" in the world.