The Lightning not only had to defend a lead in the third period Saturday against the Panthers, but as their first-round playoff series crossed over from intense to ugly, they also had to protect themselves and battle their emotions.

Tampa Bay emerged from Game 4 with a 6-2 win and a 3-1 series lead in front of a limited capacity crowd of 9,762 at Amalie Arena, but it came with a cost.

Once the Lightning took control of the game with Nikita Kucherov’s power-play goal 4:47 into the third period, the Panthers turned their focus from winning to enforcing.

One result left Kucherov, who has been the heartbeat of the Lightning this postseason, writhing in pain midway through the third after taking a slash to the back of the left knee from Panthers forward Anthony Duclair.

After several moments on the ice, Kucherov skated off, hunched over and unable to put weight on the leg. Then later in the period, defenseman Mikhail Sergachev left the game after taking a hard hit into the boards from Florida forward Patric Hornqvist.