Has there ever been a 10–3 in the La Liga?

Yes, 1 time.

The only time: October 13, 1940, Sevilla FC beat Valencia CF (Sevilla FC 10–3 Valencia CF).

Nearby scores

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