The New York Knicks and Philadelphia 76ers have expanded their rosters this summer, but the Boston Celtics remain the one-time betting favorites to win the championship at the start of the NBA season.

Boston has been the preseason title favorite for three straight seasons. The defending champion Celtics are the favorite at +290 on ESPN BETtheir slimmest preseason title chances in the last three years.

Boston has the most interest from bettors in US sportsbooks. FanDuel reported Tuesday that 43% of money bets on the sportsbook’s NBA championship odds were on the Celtics. The preseason favorites have won nine of the last 16 NBA championships.

The Oklahoma City Thunder, the Western Conference favorites, have the second-best title odds at +675, followed by the Knicks (+700) and 76ers (+825).

The Knicks’ title chances decreased in the offseason and rose from +1800 to +700 with the additions of Mikal Bridges and Karl-Anthony Towns. The Knicks attracted the second-most money from bettors on ESPN BET, behind only the Celtics. Boston hosts the Knicks in the season opener on Tuesday.

“Right now the Celtics and Thunder have the most control, but that is expected from the two teams with the lowest odds,” Halvor Egeland, trading manager at BetMGM, said in a company statement. “The Knicks aren’t a great result either.”

David Lieberman, who monitors NBA odds for Caesars Sportsbook, said he was surprised by the amount of support the Knicks have received from bettors, but noted that two West Coast teams have the biggest drag on their NBA title futures markets.

“The (Los Angeles) Lakers are usually the worst-case scenario, and that is the case again this year, followed closely by the (Golden State) Warriors,” Lieberman told ESPN. “As both are popular teams and have relatively high ratings, this is not surprising.”

The Lakers are 33-1 and the Warriors are 40-1.

The 76ers’ title chances improved from +1600 to +825 in the offseason with the addition of veteran Paul George. According to ESPN Research, these are the slimmest preseason title chances the 76ers have had since 1986.

The Brooklyn Nets enter the season with a record of 1,000-1 and are among the best players to win the title. Caesars Sportsbook reported that he placed a $750 bet in June on the Nets winning the title at odds of 1,000-1.