the one before the last

penultimate = vorletzte/vorletzter/vorletztes

Contador began the Tour de France as one of the overall favourites, but challengers to Astana rider Nibali have faded away and his grip on this year's title was strengthened further in the PENULTIMATE mountain stage.

(BBC News)

---The conversation, becoming lively as the PENULTIMATE entree was reached, had turned naturally on the affair of the theatre...

(An Old Maid, by Honore de Balzac)

It's hard to believe this is my penultimate week at the company before I retire