Last week, Walmart took another gargantuan step towards challenging Amazon’s ever-growing grip on the e-commerce world.

In an attempt to create a better deal for customers, Walmart discontinued Shipping Pass, which gave free three-day shipping for an annual fee of $49, and is now offering free two-day shipping on all orders of $35 or more. A pretty clever move, considering how Walmart’s success has historically come from offering rock-bottom prices without hurdles like a membership fee, and that the majority of online orders are well over $35.

But it didn’t take Amazon long to respond.

With a quick, quiet move over the weekend, Amazon lowered its free shipping minimum to $35.

Amazon’s free shipping rate has been one of their most popular promotions over the years, and one that has vaulted the company to its e-commerce throne. The free shipping minimum has been as low as $25 in the past and was most recently as high as $49.

Although Amazon hasn’t explicitly said so, their decision to quietly roll back the free shipping minimum to $35 without much fanfare has incited some followers to speculate if the tech company is feeling the pressure from other major retailers (notably Walmart) with lower free shipping requirements.

Either way, this is great news for Amazon sellers and has the potential to open the doors for increased sales in 2017.