Mathieu Roy scored the winner 3.8 seconds from time as Sheffield Steelers beat Hull Stingrays 3-2 to reach the Elite League play-off final.
After a goalless first period, Eric Galbraith fired Hull, who finished seventh in the league standings, ahead.
Darrel Hay found the top corner to level for the champions before Colton Fretter gave them a 2-1 lead.
Corey Tanaka made it 2-2 but Roy won it on a late powerplay after Omar Pacha was penalised for holding.
Sheffield, who won the play-offs last season, will play the winners of Saturday's second semi-final between Belfast Giants and Coventry Blaze in Sunday's final.
Hull will meet the losers of that contest in the third versus fourth play-off.