McDonald's is stepping up its chicken game. 

The chicken sandwich craze began when Popeyes unveiled its improved chicken sandwich. 

Though McDonald's has featured several chicken sandwiches on its menu for years, the company is debuting new and improved versions of old favorites to try and entice customers. 

Beginning this week, the franchise is selling its Chicken McGriddles and McChicken Biscuit sandwiches nationally for a limited time. 

They were previously available only in certain markets, but now they're available to the masses.

McDonald's has also introduced a deluxe version of its crispy chicken sandwich on a trial basis. 

The new version has tomatoes, lettuce and mayo. 

The trial sandwich is available to customers in Knoxville, Tennesse and Houston, Texas.