New York-listed supplier Scientific Games has launched sports betting in a third US state through its partnership with casino operator Caesars.

The new retail sportsbook, THE BOOK, is powered by Scientific Games’ OpenBet platform and has been rolled out at Harrah's Philadelphia Casino and Racetrack.

Initially Harrah's players will only be able to place bets at the venue, with an online and mobile sports betting offering to follow during the first quarter of 2019.

“We're excited to open THE BOOK, which allows our players to wager on their favorite professional and college sports events at the region's most complete game-changing sports betting experience,” said Christian Stuart, executive vice president, gaming and interactive entertainment at Caesars.

“We've worked seamlessly with Scientific Games to cement our sportsbook presence in new markets with great speed, and we're excited to usher in a new era of sports betting capabilities for Pennsylvania players at Caesars."

The Pennsylvania sportsbook features a wide range of betting options, including professional and college sports coverage for football, basketball, baseball, hockey, soccer, and golf.

Further enhancing Caesars’ sportsbook, Scientific Games will provide ongoing managed trading services from its Don Best group, powering the platform's pricing and data feeds.

“This is the third state in which we've launched sports betting with Caesars, following in the footsteps of New Jersey and Mississippi, and we're thrilled to see constant growth in our partnership,” said Jordan Levin, executive vice president and Digital group chief executive at Scientific Games.

“Sports betting builds more momentum every day, and we're proud to partner with Caesars to lead the charge and provide a top-notch solution to players in Pennsylvania."

Harrah’s becomes the latest venue to launch sports betting in the state, following sportsbook launches for Rush Street Interactive’s SugarHouse Casino and Rivers Casino, as well as Kambi-powered Parx Casino and South Philadelphia Turf Club. Hollywood Casino at Penn National Race Course became the first operator to launch sports betting last November.

Shares in Scientific Games Corporation (NYQ:SGMS) closed unchanged at $24.49 per share in New York Friday, while shares in Caesars Entertainment Corporation (NYQ:CZR) closed up 2.54 per cent at $8.87.