Sí, mi equipo ganó el torneo. Mi equipo = Idop (Me, Te, Le, Nos, Les) El tourneo = Dop (Me, Te, Lo/La, Nos, Los/Las)
Sí, nos lo ganó.
The boy in the green shirt is asking a football player, "Did your team win the tournament?" The football player responds, "Yes, my team won the tournament."
The athlete could say the sentence using a DOP and a IDOP. Instead of saying Mi equipo (my team) he could use a IDOP. He would want to use "nos" because he is talking about his team and including himself (he is a part of the team). Instead of saying El tourneo (the tournament) he could use a DOP. He would want to use" Lo" because the tournament is masculine and it is in the el/ella/usted form.
This is the other sentence he could have said to answer the kid in the green shirts question. It means, "Yes, we won it" The sentence uses both a DOP (lo) and a IDOP (nos)