The National Hockey League announced that the second week of Phase 4 testing has yielded zero positive results for the coronavirus. The league hasn't had a single positive test since restarting its season inside its Toronto and Edmonton bubbles.

The NHL administered 7,245 tests from Aug. 2 to Aug. 8. Daily testing was conducted for members of each team's 52-person traveling party. Along with the testing, the NHL has used a touchless biometric identification system to take players' temperatures and track health information, as well as strict social distancing and cleaning protocols inside hotels and arenas.

Phase 4 of the NHL's Return To Play protocols followed the opening of training camps in the team's home cities, which was seen as the riskiest time for potential coronavirus infections since the players were restricted only while at team facilities. But positive tests during Phase 3 were minimal, before becoming nonexistent inside the Canadian city bubbles.

The NHL chose to restart its season in Toronto and Edmonton due to those cities' low coronavirus rates, while American cities like Las Vegas were spiking at the time. Part of that thinking was that the NHL would not be taking away testing resources desperately needed by those communities since they had the outbreak under control.

Since entering the bubble, the NHL has administered 14,258 tests through Aug. 8 with zero positive results. The number of tests will begin to decline now that the opening round of games has been completed, with eight teams having left the bubbles. The quarterfinal round of the Stanley Cup playoffs begins on Tuesday.