Hibernian overcame a brave challenge from First Division St Johnstone to move into the CIS Insurance Cup final.
Steven Fletcher gave Hibs an early lead
Steven Fletcher volleyed home an early opener for the Scottish Premier League outfit after an Ivan Sproule cut-back.
Jason Scotland headed a deserved equaliser to send the semi-final into extra-time at Tynecastle.
But Saints keeper Kevin Cuthbert failed to deal with David Murphy's 30-yard free-kick and Abdessalam Benjelloun settled the game on the break.
Guillaume Beuzelin had returned to the Hibs starting line-up following the transfer to Rangers of Kevin Thomson.
Dean Shiels was also in midfield in place of young Lewis Stevenson.
Fletcher was the sole striker, but he made an impact after less than three minutes against the side on a high after defeating Division One leaders Gretna on Saturday.
Sproule sped to the by-line before flicking the ball to the Scotland Under-19 striker, who volleyed home from 12 yards.
St Johnstone showed their battling qualities and Scotland wriggled free inside the Hibs box before firing into the side-netting from 15 yards.
Hibs almost doubled their lead when Scott Brown, putting transfer speculation behind him, struck the top of the crossbar with a 25-yard drive.
But Saints, forced to do without cup-tied recent signings Willie McLaren and Derek Lilley, were menacing at set-pieces.
Abdessalam Benjelloun scored Hibs' third goal at Tynecastle
And towering centre-back Kevin James headed a couple of yards over after beating goalkeeper Andrew McNeil to a Paul Sheerin free-kick.
Beuzelin deflected another James header over his own bar and a Sheerin drive from the edge of the box flew wide as Saints began to take control.
A Martin Hardie effort from eight yards was deflected over for a corner.
And Hardie again threatened after the break, sending a hitch-kick volley just over the bar from 16 yards.
Cuthbert did well to get a hand to a Shiels effort after the Hibs forward broke clear, but it was St Johnstone who were the more threatening.
A Peter McDonald cross took a deflection before striking the top of the crossbar.
And a Derek McInnes drive from 20 yards flew inches wide with McNeil well beaten.
Saints eventually made the breakthrough when substitute Filipe Morais sent in a beautiful cross and Scotland headed over the stranded McNeil.
But Cuthbert appeared at fault at the beginning of extra-time, when he could only push Murphy's curling 30-yard free-kick into the corner of his own net.
Another Murphy effort was deflected on to the crossbar before Benjelloun rounded the goalkeeper after appearing to trip Alan McManus to end a pulsating cup tie.
St Johnstone: Cuthbert, Lawrie, McManus, James, Stanic, Mensing, McInnes, Hardie (Jackson 95), Sheerin, MacDonald (Morais 68), Scotland.
Subs Not Used: Halliwell, Anderson, Dyer.
Booked: McManus, Hardie, McInnes, Jackson, Lawrie.
Goal: Scotland 76.
Hibernian: McNeil, Whittaker, Martis, Jones, Murphy, Sproule (McCann 67), Scott Brown, Stewart (Benjelloun 46), Shiels (Stevenson 59), Fletcher, Beuzelin.
Subs Not Used: Hogg, Simon Brown.
Booked: Scott Brown, Fletcher.
Goals: Fletcher 3, Murphy 92, Benjelloun 120.
Ref: C Thomson