Trailing by a solitary goal, the home supporters raucously welcomed the announcement that there would be five minutes of stoppage time but, not for the first time, dilatory defending cost St Mirren dearly. A slovenly pass from Conor McCarthy was seized on by Sam Cosgrove, who was then brought down by Sam Foley as he burst into the 18-yard box. Cosgrove converted the resulting penalty for his 23rd goal of the season, beating Vaclav Hladky low to his left.
The visitors had the first opportunity of the evening when Curtis Main stole in front of his marker to glance a header inches wide from Dean Campbell’s inviting free-kick in the fourth minute and they did not have much longer to wait before taking the lead.
Midfielder Lewis Ferguson, supplied by Matty Kennedy, drove at the home defence, unencumbered by Saints midfielders. The 20-year-old took full advantage of their absence to curl a superb effort high past Hladky with the outside of his right boot from 20 yards.
It was to be the only attempt on target by either side during a combative first half which was high on industry but, Ferguson’s finish apart, low on artistry.
Playing against the merciless wind, the Dons had been on the front foot from the first whistle. They pressed relentlessly, snapping at their opponents’ heels whenever they had the ball and looked to put the hosts under pressure whenever they regained possession.
Niall McGinn did just that in the 24th minute, dispossessing Cammy MacPherson to leave himself with a clear run in on goal only for referee Don Robertson to harshly decree that he had fouled the latter.
Saints gradually found a way into the tie and, while they didn’t trouble goalkeeper Joe Lewis, they were at least spending more time in the Aberdeen half. The visitors appeared content to sit back against the Premiership’s lowest scorers and hit them on the counter.
There was a blow for the Dons when defender Scott McKenna hobbled off eight minutes after the restart – which could be a big cause for concern for Scotland manager Steve Clarke ahead of the Euro 2020 play-off semi-final against Israel at Hampden later this month.
Main believed he had given Aberdeen a two-goal cushion on 55 minutes when he headed home from Kennedy’s cross but assistant referee Graeme Stewart raised his flag for offside.
It took 63 minutes before winger Jamie McGrath recorded the hosts’ first effort on target with a dipping 25-yarder which failed to trouble Lewis but served as a reminder to Aberdeen that the game had not yet been put to bed.
However, while manager Jim Goodwin made substitutions, a cursory glance at his bench was enough to ascertain that game-changers were in short supply and the Buddies ran out of ideas long before the end. The 1,459 travelling fans celebrated their progress enthusiastically, although they spent almost as long taunting Steven Gerrard and Rangers about their latest cup failure.
“I thought we were the better team on the night but the fact is we conceded two poor goals,” said Goodwin.