Tanner Jeannot had two goals and two assists, Alexandre Carrier had a goal and an assist, and Filip Forsberg had three assists for the Predators. Juuse Saros made 27 saves in his first start of the preseason.
Brandon Hagel scored, and Hugo Alnefelt made 21 saves for the Lightning, who also lost 2-0 here on Thursday.
Jeannot gave Nashville a 1-0 lead at 5:54 of the first period with a power-play goal, and Carrier made it 2-0 with a power-play goal of his own at 7:00.
Colton Sissons extended the lead to 3-0 at 18:21.
Duchene made it 4-0 at 17:11 of the second period, and Jeannot scored his second power-play goal of the game at 2:26 of the third period to make it 5-0.
Hagel scored for Tampa Bay to make it 5-1 at 4:11.
Duchene's second of the game made it 6-1 at 5:09, and Zach Sanford scored at 6:33 for the 7-1 final.
