Caesar's Palace. Photographer: Jacob Kepler/Bloomberg

Eldorado Resorts found a surprising source of funds when it needed cash to finance its $17.3 billion acquisition of Caesars Entertainment Corp.: its landlord.

Vici Properties, a REIT spun off to Caesars' creditors almost two years ago, played a key role in financing the deal. The company, which already owns 21 Caesars casinos, agreed to buy three more properties for $1.8 billion. It will also provide an additional $1.4 billion—in exchange for $98.5 million a year in higher rent payments.

Over the past five years, Eldorado has used creative deals like this to transform itself from a small regional player. The transaction announced Monday catapults the little-known company into the big leagues of gambling, giving the Reno, Nevada-based operator banner properties such as Caesars Palace, Harrah's and Bally's.