With the Pistons keeping the series alive, this is the first time in 12 years that a conference has had all four first round series go at least six games.
The last time this occurred was the 2014 Western Conference first round, where 3⁄4 of the series went to seven games
Clippers over Warriors (4-3)
Thunder over Grizzlies (4-3)
Spurs over Mavericks (4-3)
and the Blazers beat the Rockets in six.
This also happened in the 2010 WC first round and the 2003 EC first round.
This is the fourth time this has happened since the first round expanded from a best-of-5 to a best-of-7.
There has never been a first round where all four series in a conference went to seven games.