Callumn Morrison put the Pars ahead in the 23rd minute but just over a minute later, a succession of mistakes in the home backline allowed Aidan Fitzpatrick to tee up Ben Stanway to net the leveller.

Both teams had chances to claim victory ahead of Friday evening’s second leg at Firhill, though neither were able to find a winner.

The hosts were without Nurudeen Abdulai after he picked up an injury in their quarter-final victory over Arbroath. The midfielder was replaced by Alfons Amade, while Shay Kearney came in for John Tod.

Thistle had been out of action for almost two weeks following their 1-1 draw with Queen’s Park. Mark Wilson made five changes from the starting XI that evening — most notably, top scorer Alex Samuel dropping to the bench as the Jags deployed a three-man attack led by Tony Watt.

Dunfermline started brightly, forcing a succession of corners before Chris Kane forced Josh Clarke into a smart low stop with a snap-shot from the edge of the box.

The opener arrived in the 23rd minute after Andy Tod latched on to a long free-kick before cutting back for Morrison to slot home.

Pars boss Neil Lennon called for calm but his side would be pegged back just 79 seconds later.

Defensive mistakes from Josh Cooper and Amade presented Fitzpatrick with the chance to feed Stanway, who kept his composure to slot beyond Aston Oxborough.

Morrison was unable to keep his volley down as the home side looked to restore their advantage.

In the 43rd minute, Matty Todd passed up a good chance when he tamely directed Morrison’s cross into the grateful arms of Clarke.

The home fans were certain they should have had a penalty on the stroke of half-time after Todd hit the deck under the challenge of Fitzpatrick. Referee Duncan Nicolson awarded a goal-kick and the crowd made their feelings known as boos rang around East End Park on the half-time whistle.

Fitzpatrick thought he had fired the Jags ahead in the 47th minute following a defensive lapse from Tod — but his celebrations were cut short by the offside flag.

Stanway was denied by an excellent save from Oxborough after Logan Chalmers forced an error from Kieran Ngwenya.

It took a good stop from Clarke to parry away Robbie Fraser’s free-kick in the 54th minute. Morrison was quickest to the rebound but after going to ground, his half-hearted appeals for a penalty were waved away.

Samuel replaced Watt as part of a triple change with 25 minutes remaining but Cooper came agonisingly close on 75 minutes after gliding past Logan before curling an effort inches wide with the keeper scrambling.

Substitute Keith Bray lashed wildly over with nine minutes remaining as Lennon’s men searched for a winner.

In the final minute, Oxborough was the hero for Dunfermline as he superbly pushed away Fitzpatrick’s goalbound strike before Samuel headed wide from close range.

The Pars keeper was caught out by Crawford’s attempt in added time but the ball trickled inches wide. Several crucial blocks from Ngwenya in added time helped the hosts hold firm.