Most of the professional leagues use Adidas, Gilbert, Mitre or Webb Ellis manufactured balls.

Entity and relation annotations:
id: 0
type: entity
value: text: Adidas
labels: <Organization>
id: 1
type: entity
value: text: Gilbert
labels: <Organization>
id: 2
type: entity
value: text: Mitre
labels: <Organization>
id: 3
type: entity
value: text: Webb Ellis
labels: <Organization>