|Location||Bear Mountain Mine|
–Sergio, confronting Red Harlow
After making it out of his jail cell in the mission "Jailbreak", Red searches the mine for several keys needed for his escape. Along the way, he enters a room with Sergio, Private Eli Hanson, and Ennio. They attempt to duel the player and are all killed in the gunfight. Sergio is also seen controling the gatling gun in the mission Fort Diego.
Sheriff Bartlett's Journal
Sergio is listed in Sheriff Bartlett's Journal on pages 182 - 183 under the Renegade Army section. The pages are unlocked by purchasing Keys from the Shop interface at the start of "Fort Diego". He is simply referred to as "The Duellist" because Sheriff Bartlett did not know his name.
- Judging by his uniform, he appears to be a member of General Javier Diego's renegade army.