Kilmarnock swept aside hapless Dunfermline to leave the Pars languishing at the foot of the SPL.
Colin Nish scored a double against his former club
Gordon Greer headed Killie into an early lead, but Stevie Crawford slotted home a quick reply for Dunfermline.
Paul Di Giacomo shot home after a fine passing move then fired in his second from long range.
Colin Nish bundled in Killie's fourth and the Pars' hopes were ended when Souleymane Bamba was sent off before Nish fired his second from close range.
Di Giacomo and former Dunfermline striker Nish had returned to Killie's starting 11 in place of the injured Gary Wales and dropped Peter Leven.
New Dunfermline boss Stephen Kenny had brought in Stephen Simmons and Greg Ross in place of the injured Darren Young and Aaron Labonte.
But the visitors looked all at sea as Kilmarnock took the lead from the first real chance of the game after just seven minutes.
A Garry Hay corner picked out Greer in front of goal and he left goalkeeper Dorus De Vries with no chance with the close-range header.
But Dunfermline refused to buckle under Kilmarnock's early pressure and were back on level terms with 11 minutes on the clock.
Defender Souleymane Bamba was sent off for violent conduct
An Owen Morrison cut-back found Crawford and he slotted past goalkeeper Graeme Smith.
But Kilmarnock had their noses back in front after 18 minutes when Hay played a neat one-two with Nish before setting up Di Giacomo for the shot.
Di Giacomo had his name on the scoresheet again in the 25th minute, sending a long-range effort past the goalkeeper.
Killie strengthened their lead two minutes later.
A Naismith effort was pushed on to the bar by De Vries, but Nish was lurking in front of goal to bundle home the rebound.
Dunfermline made their first change of the game after 30 minutes, swapping forward Freddie Daquin for defender Bamba.
The day went from bad to worse for Dunfermline when Bamba was ordered off in the 57th minute for pushing Naismith in the chest.
Dunfermline were now completely devoid of confidence and it was only a matter of time before Killie grabbed their fifth of the day.
A Greer header found Nish at the back post and he side-footed home from six yards in the 72nd minute to complete the rout.
Kilmarnock: Smith, Grant Murray, Hay, Greer, Frazer Wright, Fowler, Johnston, Invincibile (Stephen Murray 71), Naismith (Leven 77), Nish, Di Giacomo (Dodds 77).
Subs Not Used: Combe, Ford, Adams, Campbell.
Goals: Greer 7, Di Giacomo 19, 25, Nish 27, 72.
Dunfermline: De Vries, Shields, Scott Morrison, Wilson, Ross (Hamilton 78), Simmons, Mason, Owen Morrison (Labonte 59), Muirhead, Daquin (Bamba 30), Crawford.
Subs Not Used: McKenzie, Woods, Williamson, Smith.
Sent Off: Bamba (57). Booked: Ross, Mason, Labonte.
Goal: Crawford 11.
Ref: J Underhill