The turnovers and defensive shortcomings that plagued the 76ers last season were still glaring in their four preseason games. So while the expectations have changed, the Sixers' problems remain the same entering Tuesday's season opener at the Boston Celtics.

The Sixers surrendered their share of wide-open perimeter shots and, on occasion, easy baskets in the post in exhibition games against Melbourne United, the Orlando Magic, and Dallas Mavericks (two games). They also averaged 20.5 turnovers.

But turning the ball over is nothing new. The Sixers have been the league's worst team in that category in four of the past five seasons: 2017-18 (15.9 per game), 2016-17 (16.0), 2014-15 (16.9), and 2013-14 (16.4). The Sixers finished 29th out of 30 teams in 2015-16 (15.6).

"I don't know if it's the system or how much we pass the ball," center Joel Embiid said of the turnovers. "But sometimes it happens."

As they did last season, point guard Ben Simmons (4.5 per game) and Embiid (4.0) averaged the most turnovers for the Sixers in the preseason. But Embiid thinks the turnovers are something the team will get under control.

"But I think defensively, I wasn't really happy with our preseason defense," he said. "It's a new concept this year defensively, and everybody has to get on the same page."

This season, the Sixers don't want to give up three-pointers. They want their guards and forwards to run people off the line. And they want Embiid to focus on protecting the rim and stay off the perimeter.

The Celtics took advantage of drawing Embiid away from the basket en route to winning last season's Eastern Conference semifinal playoff series in five games.

"As soon as we lost, you start really paying attention and figuring out what we have … and it's been a challenge all over the place where we're trying some things out differently," coach Brett Brown said.

However, the Sixers didn't stop teams from taking three-point shots this preseason.

Melbourne got looks but just missed them in making nine of 33 threes (27.3 percent). The Magic made 10 of 24 threes (41.7 percent). Dallas hit 13 of 39 (33.3 percent) Friday in Shanghai, China. Three days later, the Mavericks sank 15 of 37 (40.5 percent) in Shenzhen, China.

The Sixers knew that their new defensive philosophy could experience some initial pain.

"But I feel like to get where we want to go, you're going to have to do that," Brown said. "We don't want to coach afraid.

"We want to be bold with what we think and why we think it and be committed to doing that."