CORK marksman Ruaidhri Keating struck in the third minute of injury time to take some of the steam out of the Saints' title chase propulsion.
The hosts looked home and hosed at Richmond Park, a ninth win in 12 under new boss Jon Daly banked and a move to within two points of pace-setters Shamrock Rovers going into the break from domestic battle to attend to European affairs.
That was until a long, hopeful punt upfield by City's reserve goalkeeper Jimmy Corcoran put the Saints' rearguard in all sorts of bother.
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The ball pinged out to the left, where three Cork players were lurking, and it was the good fortune of Liam Buckley's side that it fell to Keating.
The striker stayed cool and swept a low shot beyond Dean Lyness for an important point in City's bid to avoid a relegation play-off.
As for the Saints, it was a tough pill to swallow after Jake Mulraney's stunning 36th minute strike illuminated a scrappy first half.
Mulraney, in fact, helped make it a too hot to handle welcome for Cork's debutant keeper Tiernan Brooks.
The Leesiders only announced yesterday that Brooks, 20, had joined from Notts County and he was drafted straight in for the visit to Inchicore.
It always looked a tough assignment for the new man and for Cork against a Saints side that beat UCD 7-0 last week and is gearing up for a crack at F91 Dudelange in the UEFA Europa Conference League.
The Ireland under-21 international must have felt under siege by the end of a stoppage-ridden first half that saw six minutes of injury time added.
Brooks was injured twice in that opening period, and three times overall. Mulraney's 16th minute challenge was late and earned him a booking, but Brooks' heavy touch invited Mark Doyle's tackle before the break.
His day was done after 55 minutes, when he was replaced by Corcoran - who himself went down after a heavy collision with the onrushing Conor Carty.
He was able to continue, and perhaps Corcoran's contribution to the equaliser was karma of sorts for City's goalkeeper union.
Earlier, Brooks had pulled off an outstanding 24th minute save from Jamie Lennon, who hit a piledriver when Mulraney's shot was cleared to just outside the box.
But then 15 minutes later, Chris Forrester fed Mulraney out on the right. The 27-year-old was given too much freedom by John O'Donovan and he cut in onto his left foot before unleashed an unstoppable effort over Brooks and into the far top corner.
It was Mulraney's sixth goal of the season, and his third against Cork. For their part, the Leesiders were striving to get their twin attack of Keating and Babatunde Owolabi involved without much success.
City, however, felt they had a good shout for a penalty in the 45th minute when Cian Bargary's cross-shot struck John-Alan McGrath on the hand.
But the Saints defender's arm was down and never moved, and ref David Dunne made the right call to play on.
The injured Cork defender Jonas Hakkinen didn't return for the second half but City came close to an equaliser less than two minutes in.
At a corner, Hakkinen's replacement Cian Coleman's header was goal-bound but Anto Breslin was there to clear off the line.
Keating could have fared better seven minutes later had his shot not hit his skipper, Aaron Bolger.
After that the Saints re-established control. Carty hit the post but hope remained for Cork - and Keating seized the moment.
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