You need to be first among either the amateur or veteran Triathlon divisions (whichever you are currently in). Since you were listed as 7th, you did not win that division. This badge does not refer to any of the numeric per-game divisions but solely to the two possible triathlon divisions.

However it looks as if amateur vs veteran is VERY unbalanced right now. We do not have a single amateur player listed compared 63 veterans. Terry, care to change the boundary from 6 to 10 badges (and also including "Biggest Slice" which now should be in there) so that it would again be an actual two-division contest?

If you happen to have become a veteran prior to winning Triathlon it then becomes one of the toughest badges I can think of that involve single plays of hourlies/dailies.

It took me ages. I think I remarked at the time that there was a rather large disconnect between the difficulty experienced by new players compared to existing players who had ‘levelled up’ prior to the badge becoming available.

Speaking of Tri Badges, how are tri ties broken? Each hourly says that ties go to the player playing first, but a point tie in a triathlon is not defined how it's broken.