They have beaten them at Parramatta, Homebush, Moore Park and Penrith and now they've also beaten them even on a cricket pitch. Western Sydney Wanderers just cannot escape the grip of crosstown rivals Sydney FC.
The Sky Blues tightened their stranglehold on the Wanderers with a deserved but controversial 2-0 victory at the Sydney Cricket Ground.
It was a titanic contest between two teams whose rivalry is fierce and genuine but once again an A-League match was affected by VAR, which must be the worst idea to hit the competition since its inception in 2005.
Sydney were leading 2-0 thanks to goals early in each half from Adam Le Fondre and Alex Brosque when the Wanderers - and the crowd of 30,588 - thought they had clawed their way back into the game with a goal from Roly Bonevacia.
But the video assistant referee saw an infringement in the lead-up to the goal and asked on-field ref Chris Beath to have a look at the incident.
The goal was subsequently disallowed, much to the disgust of the Wanderers fans and coach Markus Babbel whose hot protests earned him a red card.
It was the third time in the match that VAR was called into action and for the third time players and fans had to wait with bated breath to find out if they should celebrate or not.
Regardless of whether the decision to disallow the goal was right or wrong, it is 'clear and obvious' that VAR - or rather its farcical application in Australia - is killing the game as a spectacle. It is harming the A-League's image and Football Federation Australia should scrap this experiment immediately or else they will be held largely responsible for turning the competition into a complete farce. Coaches, players, fans and media have had enough of this nonsense.
We just have to go back to square one, accept the fact that our referees are of a poor standard, hope they minimise their mistakes and get on with the games.
Refs make mistakes and we used to have a controversy almost every round in the pre-VAR days but now we have one almost every match, which would suggest that this maligned system is more trouble than it is worth.
VAR was a success at the FIFA World Cup in Russia because it was run efficiently by top class referees. We do not have that luxury in Australia.
Back to the football, Sydney are improving with every game but they are still rough around the edges and were particularly suspect in defence ... thankfully for them the Wanderers forwards were in no mood to capitalise.
It is still early days but it appears that Sydney's defence is not as compact and strong as it was under Graham Arnold in the last two seasons.
With more composure the Wanderers could have scored three or four times.
They had lots of possession and they occasionally orchestrated some incisive attacks but they all evaporated when it came to the finishing.
Sydney have lost only once in 15 matches against the Wanderers and they must feel they can overcome their neighbours any time even without playing at their best, as was the case at the SCG.
Only three weeks ago the Sky Blues knocked out the Wanderers from the FFA Cup with a 3-0 victory to set up a final against Adelaide United at Coopers Stadium on Tuesday night.
The way things are at the moment the two clubs look miles apart even though, in fairness, the Wanderers probably did not deserve to be a goal down at halftime after recovering well from the stunning opening goal after five minutes and creating and wasting two clear scoring chances through Oriol Riera and Bonevacia.
Sydney, as they do so often, took their chances well and will feel their attack is beginning to function to the desired effect.
Coach Steve Corica must be delighted with the acquisition of Englishman Le Fondre, whose mobility, passing skills and finishing are of the highest order.
Brazilian Bobo did a splendid job for Sydney in the previous two seasons but he will not be missed too much if Le Fondre continues to produce such top quality stuff.
I'd like to see him with half a dozen A-League matches under his belt.