Has there ever been a 9–0 in the Liga MX?

Yes, 2 times.

The first time: November 30, 1947, León beat Marte (León 9–0 Marte).

The last time: May 16, 1976, Pumas UNAM beat Tecos UAG (Pumas UNAM 9–0 Tecos UAG), 50 years ago.

Home wins: 2. Away wins: 0.

Nearby scores

1. 10–0 Never
2. 10–1 2 times
3. 9–0 2 times
4. 9–1 1 time
5. 8–0 7 times
6. 8–1 5 times

All games

1. May 16, 1976 Pumas UNAM 9–0 Tecos UAG
2. November 30, 1947 León 9–0 Marte