All's Fair in Love and Pickleball by Kate Spencer

Pickleball rivalry? Sure. Falling for your fake boyfriend? Now that’s a surprise.

Bex Martin’s racquet club is her entire world. But the business she inherited from her mother has started to feel more like a sinking ship. That is, until Nikolaus Karras—a former tennis bad-boy with an ego as big as his serve—makes himself at home on her courts.
 
Niko has something to prove, and a high-stakes pickleball tournament is just what he needs to get back in the game after a career-ending injury. When he is finally able to set his ego aside to ask for Bex’s help, everyone assumes that they are a couple—on and off the court.
 
But she needs the prize money to save the club, and he needs a win to restore his reputation. So now they have a fake relationship as well as a doubles partner that they can’t seem to resist. Game on!