Has there ever been a 10–2 in all competitions?

Yes, 7 times.

The first time: December 13, 1919, Racing Club beat Estudiantes de Buenos Aires (Racing Club 10–2 Estudiantes de Buenos Aires) · Primera Argentina.

The last time: December 20, 2015, Real Madrid beat Rayo Vallecano (Real Madrid 10–2 Rayo Vallecano) · La Liga, 10 years ago.

Home wins: 6. Away wins: 1.

Nearby scores

1. 11–1 6 times
2. 11–2 3 times
3. 11–3 2 times
4. 10–1 21 times
5. 10–2 7 times
6. 10–3 6 times
7. 9–1 53 times
8. 9–2 33 times
9. 9–3 12 times

All games

1. December 20, 2015 Real Madrid 10–2 Rayo Vallecano · La Liga
2. January 14, 1969 Guadalajara 10–2 Nuevo León · Liga MX
3. December 8, 1963 RC Lens 10–2 Matra Racing · Ligue 1
4. December 19, 1948 RC Roubaix 2–10 Olympique de Marseille · Ligue 1
5. April 18, 1948 Independiente 10–2 Rosario Central · Primera Argentina
6. September 22, 1929 Independiente 10–2 Excursionistas · Primera Argentina
7. December 13, 1919 Racing Club 10–2 Estudiantes de Buenos Aires · Primera Argentina