Investment bank William Blair has reached an agreement to purchase boutique advisor Inner Circle Sports , a move that will give the firm an immediate presence in the rapidly growing world of sports dealmaking. Under the agreement, Inner Circle and all 16 of its employees will move under the William Blair umbrella. Co-founders Rob Tilliss and Steve Horowitz will retain day-to-day control of the business, which will continue to operate as Inner Circle Sports for the foreseeable future. Charli xcx’