Has there ever been a 10–3 in the Primera Argentina?

Yes, 1 time.

The only time: December 8, 1976, Ferro Carril Oeste beat San Lorenzo (Mar del Plata) (Ferro Carril Oeste 10–3 San Lorenzo (Mar del Plata)).

Nearby scores

1. 11–2 Never
2. 11–3 1 time
3. 11–4 Never
4. 10–2 3 times
5. 10–3 1 time
6. 10–4 1 time
7. 9–2 5 times
8. 9–3 2 times
9. 9–4 Never