Carrie Underwood surprised husband Mike Fisher by performing the national anthem before his hockey game.

The country star stepped out on the ice at the Nashville Predators first-round Stanley Cup playoff game against the Chicago Blackhawks on Monday (17Apr17), much to the delight of the crowd.

"Please rise and welcome seven-time Grammy winner and longtime Nashville Predators fan Carrie Underwood," the announcer said to the shocked hockey fans inside the Bridgestone Arena.

Carrie's husband Mike is captain of the Predators, and he wore his number 12 jersey as she sang The Star-Spangled Banner. She then took part in the team's signature towel wave with Nashville mayor Megan Barry.

The Predators won 3-2 against the Blackhawks, increasing their series lead to 3-0, and Carrie wasted no time in sharing the celebrations on Instagram.

"#Smashville has completely gone crazy!!!! 3-0 baby!!! One more! @predsnhl," she wrote alongside a clip of her cheering after her husband's team won.

The couple has been married since 2010, and at the Grammy Awards in February (17) she said her hockey game cheering skills are some of the best.

"I’m like: ‘Yeah! Get ’em!’” she said of watching Mike play. “I’m screaming at the TV, or if I’m there I’m screaming and yelling at the refs. It’s good. I’m in it!”

And the American Idol winner has no problem with their son Isaiah following in his dad’s hockey footsteps.

“I’m pretty sure he’s going to play some hockey at some point in his life,” Carrie said. “He’s about to turn two and we’ll see what happens after that! You never know. It’s up to the good lord."