By Sam Laskaris Writer Day two of the Presidents Cup was nowhere near as successful for the Six Nations Rivermen as the tournament opening day. The Rivermen, one of seven clubs participating in the national Senior B lacrosse championships, registered a 5-4 victory over the host Oakville Rock on Sunday. The Six Nations squad, however, lost both of its matches that it played on Monday. For starters the Rivermen were downed 8-6 by the Kahnawake Mohawks, representatives of the Quebec Senior Lacrosse League, in a morning match. Six Nations was then beat 7-5 by the Edmonton Miners, champions of the Alberta-based Rocky Mountain Lacrosse League. Though the Rivermen only lost by a pair of goals versus Edmonton, the Miners were in control for the majority of the match. Edmonton kept…