Aldo Rocha's 23rd minute goal cancelled out an early Hirving Lozano strike as Leon and Pachuca settled for a 1-1 draw in the first leg of their Liga MX semifinals clash.
Hirving "Chucky" Lozano proved a nightmare for Leon's defense in the first half, and he wasted little time in getting on the scoresheet when he sent a low drive past William Yarbrough.
Luis "Chapo" Montes drew a low save from Oscar "Conejo" Perez with Leons' first meaningful chance, and moments later, La Fiera were leveled.
Aldo Rocha raced onto a one-two from Mauro Boselli and nodded past the stranded Conejo to put the hosts on leveled terms.
After the break, the pattern of Hirving Lozano continued for Pachuca, with the young Mexican international forcing Yarbrough to a save from a header.
With Pachuca clearly the happier of the two, Leon pushed forward in search for a winner. Elias Hernandez struck from distance only to be denied by a superb Conejo Perez save.
Luis Fernando Tena threw Maxi Moralez into the mix in a bid to push slightly higher up, and he, too, came close to grabbing the winner, as Conejo added to his collections of saves.
At the final whistle, Pachuca earned a vital away goal ahead of Sunday's second leg at the Estadio Hidaldo.