Thematic tournament with 5(1)->2 format includes two games per opponent?

I finished a game in a "5(1)->2" thematic tournament and then the system initiated a second game agains the same player. I can't find in the Tournament Help why the second game against the same opponent started, but from perusing crosstables it appears that this is normal.

Why is there a second game and is this documented somewhere?

The tournament is named “The Sniper” with the format mentioned above, and originally noted as "approximately 4 games" or similar (can't find that now but that's what would be expected from the format).

All tournaments have 2 games per opponent I believe.

I see now.

I thought, according to the Tournament Help page http://www.chess.com/tournaments/help, the "(1)" means one game against each opponent (so did the "approximately 4 games" in my misunderstanding, but maybe it says "4 games at a time" -- as mentioned I can't find that info now). 

But looking at this wording from the above referenced page I see this was a misreading:

"Example 1: 5(2)->2+ means 5 players per group, playing both games per opponent at the same time, 2 players advance from each group, and no tie breaks."

"Example 2: 8(1)->1 means 8 players per group, playing one game per opponent at a time [without referring to the info I quote in the next paragraph, I forgot that evidently all tournaments are double round robins], 1 player advances from each group, and use tie breaks."

Elsewhere on that page it does say, "Chess.com uses the popular and easy-to-understand Round-Robin format for chess tournaments. In round-robin tournaments each player plays every other player in two games (once as white, once as black)."

Perhaps it would help to clarify that this refers to a double round-robin. 

(Hmmm bolded text in my edited msg not showing up as bolded.)

It means one concurrent game, so both games are played, but the second doesn't start until the first is finished.