Formula 1's motorsport managing director Ross Brawn says last weekend's Mexican Grand Prix is evidence the championship's 2021 aero regulations cannot be introduced soon enough.
Last weekend's race looked set for an exciting climax as different strategies among the frontrunners unfolded, with Lewis Hamilton leading Sebastian Vettel, Valtteri Bottas and Charles Leclerc.
However, in the end none of them even came close to passing one another, despite big discrepancies in tyre life.
Brawn said that proved it is still difficult for drivers to follow one another, despite the aero changes introduced for 2019.
"It's a shame that there was not much of a fight on track," he said in F1's post-race media address.
"Especially among the leaders, as everything was in place to deliver an exciting fight, revolving particularly around the potential duel between Mercedes and Ferrari on a track where overtaking is very possible.
"However, once again we saw that when cars and drivers are evenly matched, then it becomes really hard to not only overtake but to even get close to the car in front.
"Getting too close for a few laps could mean ruining your tyres, causing drivers to back off and let them recover before making another brief assault.
"This is nothing new, but it confirms once again that there is a need for a change in the regulations to enable cars to fight at close quarters.
"Change is potentially now not far off, at least on paper, given that in a few days, the FIA World Motor Sport Council will rule on the regulation package for 2021, which we presented along with the FIA."
F1's big teams have pushed for fewer changes, and at the most recent 2021 meeting Christian Horner suggested the new rules should be postponed until '22 to allow more time to refine them, while at the same time giving the '21 cost cap time to kick in.
But Brawn insisted there should be no delay.
"The new aero configuration has been developed to reduce the impact of following another car," he said.
"Overtakes and battles are easy when there is one-two seconds lap time difference, but when there is a smaller difference there is no chance.
"Suggestions we should delay the introduction are frustrating because the situation gets even worse each year with the cars we have now.
"How many opportunities have we lost to see close battles? On Sunday there weren't many, despite the track characteristics and the introduction of an additional third DRS zone.
"If even these attributes do not produce closer racing, it's time we reacted.
"It isn't about change for the sake of it, we have put a massive effort into developing these new regulations in the long-term interests of the sport."