The manager demanded his side get their title defence back on track with three points against Killie, but Jim Jefferies’ side arrived in form and determined to cause another upset.
And they threatened early on when Colin Nish intercepted Fernando Ricksen’s headed backpass after just five minutes.
But the left winger opted for a first time volley, when he actually had time to take a touch, which screamed past Waterreus’ left hand post much to the disgust of his manager.
Franny Jeffers and Dado Prso complimented each other well in the 3-2 win over Porto and started brightly again together at Ibrox making a telling contribution in the opening spell.
After seven minutes Ferguson’s chip into the Killie box was well controlled by Namouchi and when he nodded the ball goal-bound, Jeffers met it at the front post to try a glancing header.
But Alan Combe was equal to the Scouser’s effort and pawed it around his post.
Although the resultant corner was initially cleared, the ball found it’s was back to Peter Lovenkrands who had remained on the right flank and when he burst into the box, Killie defender Garry Hay chopped the Dane down.
Callum Murray pointed straight to the spot and with Nacho Novo on the bench, Prso duly stepped up to send Combe the wrong way.
Despite the good work up front, however, Gers’ defensive frailties still loomed large and with quarter of an hour gone Killie won a corner.
There were two goals lost from flag-kicks mid-week against Porto, but Kris Boyd still managed to lose his marker to get a clear header in on goal.
Thankfully for the home side it went well over the bar, but 60 seconds later Danny Invinsible was brought down by Bernard to give the visitors another attacking set-piece.
This time left-footer Hay curled his shot around the Rangers wall and only a brilliant one-handed save from Waterreus denied the equaliser.
At the interval Novo came on to replace Jeffers and having been left out of the last two starting line-ups clearly felt he had a point to prove.
In the 49th minute – after a quick free kick from Ferguson – the Spaniard broke down the right and delivered a wicked cross, which Lovenkrands headed back across goal. But Gordon Greer nipped in front of Namouchi before he could pull the trigger.
Quick free kicks were the order of the day and Novo didn’t hang around in the 53rd minute when he found Prso but the Croatian’s shot swerved wide.
The former Dundee striker was in the thick of the action again immediately afterwards when he collected Ricksen’s long ball forward. With a clear sight on goal, however, he blasted over the bar with just the keeper to beat.
Thomas Buffel was introduced to the action after an hour and his pass to Prso was laid into the path of Lovenkrands.
With the Killie defenders backing off the Dane burst into the box and Alan Combe made another decent save to deny a sure goal.
But two minutes later there was nothing the former Dundee United stopper could do when Barry Ferguson scored Gers’ second.
Some neat play between Buffel and Lovenkrands on the edge of the Killie box released Ferguson who slid a left-foot shot low into the net.
Marvin Andrews came on to one of the biggest cheers of the day for his first appearance since August 20, but it was his equivalent at the other end who got on the scoresheet, albeit with an own goal.
In the 80th minute Buffel used great skill to send Ferguson into the Killie box and the skipper’s drive across goal was turned into the net by Greer.
RANGERS: 25- Waterreus; 2- Ricksen, 16- Rodriguez, 14- Kyrgiakos (Andrews 70), 3- Bernard; 31- Namouchi (Buffel 59), 6- Ferguson, 24- Murray, 26- Lovenkrands; 9- Prso, 21- Jeffers (Novo 46)
SUBS: Klos, Malcolm, Smith, McCormack
KILMARNOCK: 1-Combe; 2-Fowler, 6- Ford, 5-Greer, 3-Hay; 11- Invincible, 7- McDonald, 16- Dodds, 15- Nish (Naismith 67); 12- Johnston (Leven 78), 9-Boyd (Wales 72)
SUBS: Smith, Dillon, Leven, Hamill, Lilley
REFEREE: Callum Murray
MAN-OF-THE-MATCH: Barry Ferguson