James Scanlon's first League Two goal on his home debut helped high-flying Swindon see off Oldham.
The Manchester United loanee fired in from an acute angle in the 23rd minute after Aaron Drinan chased a ball down the channel and hooked it back.
Michael Olakigbe should have put the Robins ahead early on but failed to get proper contact on Ollie Palmer's tempting cross.
Joe Snowdon then won the ball, drove forward and sent a shot just wide.
Swindon ramped up the pressure after the break and a flowing move saw Fletcher Holman fire home from Snowdon's rebound to double the lead in the 73rd minute.
Seven minutes later, Oldham were awarded a penalty when Mike Fondop was hauled down, but goalkeeper Connor Ripley saved Calum Kavanagh's effort with his legs.
The busy keeper then saved three times in one hectic spell from Kane Drummond, Jamie Robson and Fondop before Drinan tapped in a late third from Junior Hoilett's cross to complete the rout.
Report supplied by PA Media.
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