SHEFF WED: Grant, Simek, Purse, Beevers, Spurr, Johnson (Esajas 62), Potter, O'Connor, Tudgay,Varney (Clarke 69), Soares. Subs Not Used: O'Donnell, Buxton, Hinds, Jeffers, Gray.
TOON: Harper, Simpson, Coloccini, Steven Taylor, Jose Enrique, Guthrie, Nolan, Butt, Gutierrez (Pancrate 64),Harewood (Lovenkrands 84), Ameobi (Carroll 73). Subs Not Used: Krul, Ryan Taylor, Kadar, Ranger.
Att: 30,030
O'Connor's goal spared managerless Sheffield Wednesday the indignity of a club-record sixth successive Championship home defeat, and let two points slip in our promotion battle.
Luke Varney opened the scoring to put Wednesday ahead in the 14th minute but Kevin Nolan and Shola Ameobi hit back in quick succession to put the Magpies 2-1 up.
Yet Wednesday refused to surrender and were rewarded in the 59th minute when O'Connor fired home from six yards to earn his side a precious point in their battle against the drop.
The Owls have now gone 10 Championship games without a victory, but they at least stopped the rot on home soil to leave Newcastle frustrated.
This was the Magpies 10th game without defeat since losing at Scunthorpe on October 20 but the hosts worked hard for a deserved point.
Chris Hughton was forced into one change from the side which beat Middlesbrough last weekend with skipper Nicky Butt replacing Alan Smith.
Wednesday sought to put their recent troubles behind them inside the opening minute when former Liverpool midfielder Darren Potter smashed a fierce shot goalwards from 20 yards out.
Butt made a typically brave block to avert the danger but the Owls continued to probe and fashioned a decent opening a minute later.
Highly-rated full-back Tommy Spurr flighted a dangerous cross into the heart of the visitors' penalty box but Jose Enrique cleared the ball for a corner which Wednesday could not make pay.
It came as no surprise when Varney opened the scoring for Wednesday in the 14th minute with a fine header from O'Connor's right-wing cross.
Yet Newcastle showed their pedigree by hitting back with two goals in four minutes to forge ahead by the midway point in the first half.
In the 19th minute, Danny Guthrie spotted Nolan making tracks inside the home penalty box and he flighted in a cross from the right which the former Bolton captain dispatched with a firm header for his 11th goal of the season.
The goal lifted Newcastle and they struck again three minutes later when Jonas Gutierrez played an intelligent pass into Ameobi from the left flank and the homegrown striker rifled home a clinical right-foot shot from 18 yards.
Butt then warmed Owls goalkeeper Lee Grant's hands with a long-range strike as Newcastle sought to claim a killer third before half time.
The closest Wednesday came to a first-half equaliser was Jermaine Johnson's shot which flashed wide in the 42nd minute.
Three minutes after the restart, Wednesday sought an equaliser when Steven Taylor was forced into a fine block to deny Varney from close range.
Johnson then fired wide for the Owls but their pressure told shortly before the hour mark when Varney headed a high ball into O'Connor's path and he rifled home a clinical right-foot drive from six yards.
Newcastle goalkeeper Steve Harper was left appealing in vain for a foul in the build-up.
Harper then did superbly well to parry Marcus Tudgay's header and Grant did likewise to deny Ameobi.
Both sides continued to push hard for a winning goal but it never came as the points were shared.