There’s a storm brewing in the rarefied air occupied by the priciest of the travel-rewards cards.

The usually-staid space, inhabited by the likes of the American Express Platinum card and top-of-the-line cards linked to the loyalty programs of American, Delta, and United, got a competitive jolt in August, when Chase released what some have called the best-ever travel-rewards credit card. Like other cards in the space, the new Chase Sapphire Reserve Visa card comes with a sky-high annual fee ($450) offset by an ultra-long list of travel perks. Oh, and for a limited time, it comes with a hefty 100,000-point sign-up bonus.

In what may be just the first in a wave of competitive countermoves, American Express has made a significant adjustment to its Platinum card perks. From today’s news release:

Today American Express is announcing an expansion of the travel benefits that have helped make the Platinum Card the category leader for more than 30 years. Beginning October 6, consumers with a Platinum Card from American Express will receive 5X Membership Rewards points on airfare booked directly with airlines or through American Express Travel.

So, five Membership Rewards points for every $1 spent on airfare. And it’s not just a temporary category bonus, in effect for a month or a quarter; it’s ongoing. And the most important comparison: Airfare spend with the new Sapphire Preferred card earns three points per $1. So Platinum trumps Sapphire on airfare spending. However, Sapphire cardholders earn three points per $1 on all travel and dining, not just airfare, whereas Platinum cardholders earn just one point per $1 on non-airfare spend. Yes, it’s complicated.

For now, it’s more of a kerfuffle than an all-out battle for the hearts and minds of rewards-focused consumers. But it’s clear from this move that American Express views the new Sapphire Preferred card as a real threat to the Platinum card. And they’re probably smart enough to realize that increasing the earnings for airfare won’t be enough to establish that card’s dominance over the long run.

In other words, there’s likely more good news for consumers ahead, as Chase and American Express vie to out-enhance each other’s premium cards.

After 20 years working in the travel industry, and almost that long writing about it, Tim Winship knows a thing or two about travel. Follow him on Twitter @twinship.

This article first appeared on SmarterTravel.com, where Tim is Editor-at-Large.