Mastercard (MA) stock plummeted 5.68% in Friday's trading session, reaching its lowest point in over five weeks. The sharp decline comes as the payment giant faces potential new competition in the lucrative card rewards market.

The sell-off intensified after news broke that Coinbase, in partnership with American Express, is set to launch a new Bitcoin rewards card this fall. The Coinbase One Card will offer up to 4% back in Bitcoin on every purchase, potentially challenging traditional credit card reward programs offered by companies like Mastercard. This development could be seen as a threat to Mastercard's market share in the highly competitive payment card industry.

Investors appear to be reacting to the growing trend of crypto exchanges entering the traditional payment space. With Coinbase's move following similar initiatives by other crypto platforms like Kraken and OKX, there's increasing pressure on established payment networks to innovate and retain their market position. The steep drop in Mastercard's stock price suggests that market participants are reassessing the company's growth prospects in light of these emerging competitive challenges.