Here are four key talking points from a Rangers perspective after a 4-0 defeat at Celtic Park.

Attitude, effort and application

Right from the start, Celtic lived up to their manager Ange Postecoglou's 'we never stop' mantra. The minute a ball went out of touch or play was halted for an infringement, Celtic were jolted to life. There was an intensity and commitment to their play that went beyond tactics - they simply looked like they wanted this result more. Rangers on the other hand, were unprofessional in the build-up to the first two Celtic goals, switching off at key moments. Ryan Kent was amongst the guilty parties in both instances and must look to get his spark back in these games if his side are to improve. The fourth goal, a gift from Jon McLaughlin to David Turnbull when he slackly tried to pass the ball out from the back, summed up the entire afternoon. 

Rangers look taken aback by 'shock and awe'

Rangers looked shocked at the tempo they faced, looking transfixed by the movement and ingenuity in front of them. It, of course, wouldn't have been a surprise - Celtic play the same way every week - but they failed to do the basics in a manner that reflects poorly on the squad. They shouldn't need a manger to prepare them for a Parkhead onslaught and switching off to Celtic's first 30-minute shock and awe tactic was only ever going to lead to one outcome.

READ MORE: Rangers detailed player ratings as Jon McLaughlin howler sums up Celtic horror show

Jon McLaughlin off the pace

Better Rangers teams than this one have often needed a big goalkeeping performance to keep them alive in the Parkhead maelstrom. History shows us the narrow margins in these fixtures mean the men in between the sticks can end up defining the fixture. Today, Jon McLaughlin didn't exactly stand tall before giving David Turnbull a wince-inducing gift for the fourth. All three of Celtic's first-half goals could be described as preventable with the first slipping from his grasp, the second coming from an acute angle and the third straight at him. You'd have to imagine the watching Allan McGregor will be expecting to win his place back for the midweek Champions League clash with Ajax.

Van Bronckhorst faces huge week

The Dutchman struggled with the Scottish Premiership last season and with his side now five points adrift after five games this term, it already looks an uphill battle to regain the title. A pragmatist with a normally sharp tactical mind, van Bronckhorst's quality as a coach is not in question but his suitability to create a consistent philosophy to win every week in Scotland is still very much up for debate. In an age where consistency of message and philosophy is seen at most top clubs, there will be a suspicion that van Bronckhorst is unsuited to the domestic task he is charged with. The manager now faces two daunting away trips, first in Amsterdam against Ajax then, even more importantly, against Aberdeen in what is sure to be a powder keg at Pittodrie. He must prove his mettle or the repercussions will be severe.