Only five players have hit three home runs in a game while a member of the Padres. One of them did it twice; I'd tell you who, but this is a quiz. One of them is fairly common knowledge, and three of the others can probably be ascertained with minimal guessing if you don't recall them doing the deed; there's only one player who I think will stump most people.
Since there are only five answers, I put just a minute and a half on the clock, which comes out to 18 seconds per answer; that will give you plenty of time to guess the ones you didn't get automatically. To help you out I've provided the year of each player's big game(s). As per usual, last names are all that are required of you.
Once you're done, log your score in the poll provided, and be mindful to use the spoiler bar feature over any relevant names in your comments.