Dundee United had to settle for third spot in the Championship and a return trip to Cappielow after this draw with Morton.
The result, combined with Falkirk’s win at Dumbarton, meant the Tangerines will head back to Greenock on Tuesday night for the first leg of the quarter-final against fourth-placed Ton.
After completely dominating the first half, they fell behind to a header from former United man Kudus Oyenuga seven minutes into the second period.
Blair Spittal dragged them level with a shot from 10 yards on 63 minutes and the fightback was on.
However, they just couldn’t find the winner they wanted, albeit the Bairns took care of business across the Clyde anyway.
The Tangerines made only one change to the line-up that started against Dumbarton last week.
Out went the suspended Simon Murray and in came Ali Coote, with William Edjenguele still banned.
On a beautiful, sunny day by the Clyde, Tony Andreu go the match under way for the Tangerines.
The visitors made a confident start, stroking the ball about well in the first few minutes.
Andreu had a pop at goal from 20 yards on seven minutes but the strike was blocked by Tom O’Ware.
On 14 minutes, the Tangerines came close to getting the opener when a Blair Spittal corner from the right was nodded goalwards by Mark Durnan. The ball reached Durnan’s fellow defender Coll Donaldson just a couple of yards out but his header was saved by Ton keeper Bryn Halliwell.
It was then the turn of Wato Kuate to have a go for United but his low drive was saved by Halliwell.
With 23 minutes on the clock, Kuate gave the ball away in the middle of the park and Morton’s break upfield ended with keeper Cammy Bell saving well from ex-Tannadice player Oyenuga.
Five minutes later and it was United’s turn to attack, with striker Thomas Mikkelsen’s glancing header going just wide after he was found by Stewart Murdoch’s cross.
The Dane was looking dangerous and on the half-hour he received the ball with his back to goal, spun around and his shot struck the base of the post after wriggling through Halliwell’s arms.
Andreu then broke clear for the Tangerines but ballooned his shot over then the French almost got a toe to Murdoch’s cross to the near post.
With 39 minutes and United continuing to press, they hit the woodwork for a second time.
This time the unlucky man was Andreu, who smacked a 25-yard shot off the crossbar.
Good work from Coote helped cut open the home defence and first Andreu had a close-range shot blocked then Jamie Robson blasted over.
Andreu, who seemed to be everywhere for the Tangerines, spun and sent a left-foot strike over just seconds before the half-time whistle blew.
All that was missing from a fine first-half display from United was a goal and they had to find at least one in the second period.
However, they were hit by a classic sucker punch as Morton took the lead on 52 minutes.
The ball was swung over from the left by Mark Russel and Oyenuga sent a looping header beyond the reach of Bell.
United tried to fight back and Robson’s header on 61 minutes wasn’t too far away.
Just two minutes later, they were level.
It was Andreu who was the creator, cutting the ball back to an unmarked Spittal to find the net with a shot from 10 yards.
On 67 minutes, Mikkelsen sent a diving header wide of the Morton post then the striker was through on goal but he took a poor first touch and Halliwell was bale to save.
The hosts changed their goalkeeper, with Jamie McGowan replacing Halliwell, while United brought on Charlie Telfer for Coote on 71 minutes.
There was yet another golden opportunity for the visitors when Spittal raced into the box from the left but his shot was saved by replacement goalie McGowan.
Scott Allardice came on for Kuate, who had just been booked, while United pushed defender Durnan up front for the closing stages.
Andreu volleyed over with five minutes left before sub Allardice blasted wide.
It was all in for United now and Andreu sent his shot over after the ball bobbled about the Morton box.
They brought on Alex Nicholls for Willo Flood but it was Morton who broke forward and sub Nesbitt saw his shot pushed on to the post by Bell.
McGowan had to push away a Nicholls chip as United continued to press but news came through from Dumbarton and it was game over anyway.
Attendance: 2,158.
Greenock Morton: Halliwell (McGowan 70), Lamie, O’Ware, Doyle, Forbes (Tidser 58), Oyenuga (Nesbitt 86), Scullion, Russell, McDonagh, A. Murdoch, Strapp. Subs not used: McGowan, Lindsay, Donnelly, Langan, Tiffoney.
Dundee United: Bell, Durnan, Donaldson, Spittal, S. Murdoch, Flood (Nicholls 89), Kuate (Allardice 80), Mikkelsen, Andreu, Coote (Telfer 71), Robson. Subs not used: Long, Dillon, Dixon.
Referee: John Beaton.