BOSTON -- Florida Panthers star Matthew Tkachuk says he doesn't believe his team is an underdog against the Boston Bruins in their first-round playoff series -- because that label would put it too mildly.

"It's probably more spoiler at this point," Tkachuk said Monday before Game 1 of their Eastern Conference series. "I don't even know if 'underdog' is a right phrase for us right now, going against that talent and everything they've done this year over there. We have our hands full. We got to play very, very, very well -- if not perfect -- to win a game [in this series]."

The Bruins set NHL regular-season records for wins (65) and points (135) in winning the Presidents' Trophy for the league's best record.

"It's going to take pretty much a perfect effort to win one game in the series against everything they have over there, with the season they've had," said Tkachuk, who led the Panthers in scoring. "I think everybody knows they've had the best season in NHL history, so it's a great challenge for our team."

The Panthers battled into the last week of the season to make the playoffs. They finished in the final wild-card spot thanks in part to goalie Alex Lyon, who won six of eight games down the stretch to earn the start in Game 1 over veteran Sergei Bobrovsky.

"I've got two good goalies, and I'm comfortable with either of them. But Lyon deserves to start," coach Paul Maurice said.

The Bruins' goaltender for Game 1 is more of a mystery. Coach Jim Montgomery said Monday that an illness is ripping through his locker room. Whether it's sickness or a lower-body injury he suffered late in the season, goalie Linus Ullmark is a game-time decision for the Bruins. Montgomery said backup Jeremy Swayman is also under the weather.

The Bruins called up Brandon Bussi from AHL Providence as an emergency third goaltender for Game 1.

Montgomery said the same for Patrice Bergeron, who has been missing from Bruins practice for multiple days. Although Montgomery said Bergeron was under the weather, the team captain also left a game early, having missed the majority of their regular-season finale against Montreal after an upper-body injury in the first period.

"The luxury we have is that we have incredible depth. Whoever ends up being healthy enough to go tonight, we know we're going to have an opportunity for success if we play Bruins hockey," Montgomery said.