Hornqvist scored on the power play to tie it 3-3 at 6:25 with a redirection of a shot by Yandle.
"We had a great pace to start the game, played with great purpose," Panthers coach Joel Quenneville said. "Nice to see the power play get a couple. Still, we had looks later in the game that we could've gotten the puck to the net a little bit more."
Lightning defenseman Ryan McDonagh did not play after the first period because of a lower-body injury. Cooper did not have an update.
"[McDonagh] eats a lot of minutes for us," Killorn said. "But I was pretty happy with the way the guys stepped up. I saw [Cal Foote] playing great on the PK and filling that role, but all the [defensemen] as a collective had to step up because McDonagh plays so many minutes."
Video review at 1:57 of the third period confirmed the call on the ice that Panthers forward Anthony Duclair's one-handed shot on the rush did not cross the goal line. Duclair and Lightning forward Anthony Cirelli slid through the crease, with Cirelli pushing McElhinney into the net.
"I saw a couple of different angles on it, and just using common sense that the area where the puck appears in afterwards was vacant," Quenneville said. "And the next picture, the puck you can argue was still over the line. It's not conclusive, but there's no puck there when you see the area, and all of a sudden that same area … common sense says it has to be in the net."
NOTES: MacKenzie Weegar had his seven-game point streak end (one goal, eight assists). The streak tied Yandle's from Oct. 24-Nov. 11, 2018, for longest by a defenseman in Panthers history. … Verhaeghe has eight points (four goals, four assists) in the past seven games. … Panthers center Aleksander Barkov had two assists and has 10 points (five goals, five assists) in the past six games. … Florida went 4-for-5 on the penalty kill and is 18-for-19 (94.7 percent) in its past five games. … Point has six goals in his past eight games. … Lightning forward Steven Stamkos had his six-game point streak end (four goals, four assists).