Mike Fisher, the star center Underwood wed last year, was shipped from the Senators to the Predators, who skate in country music's capital.
"We were seeking a top-six forward, and Mike Fisher was the player we set our sights on," Predators President David Poile said. "Mike's playoff experience will be invaluable to our team, and he immediately makes our team stronger and deeper."
Underwood recently told Detroit radio station WYCD that she and her husband love te Tennessee town.
"We both love Nashville," she said. "I envision myself living there long after I have kids and long after I'm done singing and all that stuff, just because it's a great place to live.
"You can work, you can write, you can record, you can shoot videos and all that stuff, but you can also find land and spread out a bit."
The couple wed in Georgia last July.