Question

Los jugadores __________ (jugar) en la cancha

Answer 1

Juegan
1. Take the infinitive - Jugar
2. remove the 'ar' - Jug
3. Jugar has a 'u -> ue' stem changer - Jueg
4. 'Los jugadores' are plural and in the third person, so we add the proper 'ar' ending, 'an' - Juegan

Answer 2

juegan is the answer to the blank if it is regularly conjugated but in other forms it is something else if u need that just comment