A dreadful error from Manuel Lopez Mondragon handed Tigres Monterrey a place in the Mexican Apertura final at the expense of Queretaro on Sunday.

After a goalless first leg in Queretaro, the tie remained level until the 44th minute of the second game when Lopez Mondragon scored an embarrassing own goal.

Tigres forward Damian Alvarez created space on the left to curl over a cross which bypassed his team-mates and took a bounce on its way through to Lopez Mondragon.

The unchallenged defender had time to control and turn before clearing but instead stooped and headed the ball low into the bottom right corner from eight yards.

Goalkeeper Liborio Sanchez scrambled desperately across his goal in vain, while Lopez Mondragon's pained expression told of his agony. It proved to be the only goal of the tie.

Hector Mancilla should have doubled Tigres' lead just before the hour mark but saw his penalty saved by Sanchez. Queretaro's Ricardo Vazquez was sent off in the last minute.

Tigres will face Santos Laguna in the final, with the final to be played over two legs on Thursday and Sunday.