• Tkachuk's goal - his second of the game - equalled the NHL record for the latest series-winning goal in regulation time.
• The start of the Finals will be confirmed after the Vegas-Dallas series is decided.
Matthew Tkachuk scored a last-gasp winner to send the Florida Panthers to the Stanley Cup Finals for the first time since 1996.
Tkachuk's goal, with just 4.9 seconds remaining, gave the Panthers a 4-3 win over the Carolina Hurricanes and sealed a 4-0 clean sweep in the Eastern Conference Finals.
They will face either the Vegas Golden Knights or Dallas Stars in the Finals.
Vegas currently lead their best-of-seven series 3-0.
Tkachuk's goal - his second of the game - equalled the NHL record for the latest series-winning goal in regulation time, matching Nick Metz's winner when the Toronto Maple Leafs secured a Stanley Cup Finals berth in 1942.
It was the 25-year-old American's ninth goal of the play-offs and his third winning goal of the series against the Hurricanes.
"We are lucky to have Chucky on our side," said Panthers goalkeeper Sergei Bobrovsky.
"He's been great for us all season long and the whole play-offs. He knows how to score big goals."
Anthony Duclair and Ryan Lomberg also scored for the Panthers, while the Hurricanes' goals came through Paul Stastny, Teuvo Teravainen and Jesper Fast.
Florida's last trip to the Finals 27 years ago saw them beaten 4-0 by the Colorado Avalanche.
"We know this opportunity doesn't come all the time, and the guys are so motivated to make this count," Tkachuk said. "That's so exciting."
Vegas will hope to wrap up their series win over Dallas in game four on Thursday.
The start of the Finals will be confirmed after the Vegas-Dallas series is decided.