Ayr are riding high at the summit of the Championship and the manner of this victory surely fired a warning to their rivals who have been caught cold by the league’s new boys.
Alan Forrest started the rout with a double, Lawrence Shankland grabbed his 12th goal of the season, and Michael Moffat heaped more misery on his old team with a late fourth.
Dunfermline managed only a Jackson Longridge consolation and their manager Allan Johnston admitted: “It was nowhere near good enough.
“Shankland was the difference between the teams. He ran amok, bullied our centre-halves and was a constant threat.”
Ayr raced into attack from the kick-off and after only two minutes Robbie Crawford had a header from an Andy Geggan cross touched past.
Dunfermline found themselves a goal behind three minutes later when great work by Moffat ended with a pinpoint cross which Forrest headed into the top corner.
The Pars went close through Andy Ryan before Danny Devine had a netbound header punched over the top by Ross Doohan.
Devine, who had earlier been booked, reacted angrily when he was replaced on the half hour by Myles Hippolyte.
Ayr then left the Fifers in disarray when they destroyed them with two goals in as many minutes.
Forrest played a 1-2 with Shankland before firing home his second from close range.
Six minutes before the interval, Shankland, pictured, went from provider to scorer when he knocked home Ayr’s third goal from Crawford’s service.
Dunfermline must have been relieved to seek the sanctuary of the dressing room after a miserable first-half performance.
They claimed a penalty two minutes after the restart when Ryan went down under a Jamie Adams challenge.
Jackson Longridge, on his return to his old stomping ground, threw them a lifeline after 55 minutes when he collected a Hippolyte cross and fired under Doohan who had been bidding for a club record-equalling eighth consecutive clean sheet.
But Moffat sealed Ayr’s success nine minutes from time after sub Declan McDaid and Shankland set him up.
Strangely, Ayr boss Ian McCall claimed he didn’t enjoy the match despite the comprehensive winning margin.
He said: “It’s my fault that we didn’t water the pitch, which meant the surface was sticky and didn’t let us play like we can.
“Shankland is beating himself up in the dressing-room. Their three centre-halves, who are all good players, couldn’t handle him.”