Queen of the South progressed to the fifth round of the Scottish Cup with a convincing 4-0 win over Junior side Linlithgow Rose at Palmerston Park.
After 17 minutes, Stephen Dobbie launched in a powerful shot to open the scoring for the home side.
Jim Thomson added a second with a headed-in corner after 22 minutes.
The third arrived just before half-time through O'Connor's low drive and Stuart McArthur deflected in Stevie Tosh's fine solo effort to make it four.
Linlithgow boss Jim Sinnet was full of praise for his players and lamented a possible handball in the lead up to Dobbie's opener.
He said: "I think we deserved a goal but we didn't manage to get it.
"The first goal was tough to take because we thought it was handball and it was a crucial goal. It was a turning point.
"I thought up to that point we had played well and had plenty of the ball.
"When we lost that goal it made it much more difficult because they are full time and it took the pressure off them."
Linlithgow's only significant threat of the early action came in the 16th minute when a clever lay-off from Brian Carrigan allowed Andrew Dick to produce the game's first shot on goal.
Less than a minute later the visitors found themselves trailing when Thomson's long ball was flicked on by O'Connor and Dobbie fired low into the bottom right-hand corner of the net.
Gordon Chisholm's men doubled their lead six minutes later when Thomsom easily headed down Robert Harris' in-swinging corner.
Queens came close to adding a third after 32 minutes when former Hearts midfielder Neil MacFarlane picked up a loose ball on the edge of the box, but sent his effort over the bar.
Shortly before the break, Dobbie set up O'Connor in his 100th appearance for the Dumfries club, and he made handed his side a 3-0 lead heading in for the interval.
The visitors made a bright start to the second half and went close to scoring in the 52nd minute when Carrigan's free-kick struck Jamie MacDonald's bar.
Tosh, who was critical of the decision to allow Junior sides in the Scottish Cup earlier this week, sent a Queens free-kick narrowly over the bar.
But the home side's victory was complete when the fourth goal arrived in the 73rd minute after Tosh's shot across goal was deflected into his own net by McArthur.
Queen of the South: MacDonald, McCann, Harris, Aitken, Thomson, MacFarlane (O'Neill 80), Gilmour, Tosh (Paton 82), Burns, O'Connor, Dobbie (Stewart 75). Subs Not Used: Grindlay, McQuilken.
Booked: MacFarlane.
Goals: Dobbie 16, Thomson 22, O'Connor 40, McArthur 72 og.
Linlithgow Rose: Logan, Gallacher, McDermott, Donnelly, Hogg, Bradley, Dick (Burnett 70), McArthur, MacSween (Feeney 76), Carrigan, Herd (Donaldson 84). Subs Not Used: Pinkowski, Wilson.
Booked: McArthur.
Att: 3,062
Ref: J Underhill
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