Auburn Hills -- The sample size is still small, Dwane Casey reminded on Friday, but the early passing numbers are concerning for Detroit’s first-year coach.

The Pistons, winners of four straight to open the season and losers of three straight since, are last in NBA in assists with 19.1 per game.

“Let’s look at things 15-20 games in and see if those still hold true,” Casey said after practice Friday, as the team returned home after Wednesday's loss at Brooklyn and are flying back east to Philadelphia for the final leg of a three-game road trip. “We want to make sure the ball is moving.”

The Pistons are the only team in the NBA who haven’t had a player tally at least seven assists in a game this season. Phoenix (1-6) is the only team with seven as their season high, while every other team has had a player get at least eight.

For each game in Detroit’s current three-game losing streak, the team-high has been four assists, while six was the team-high in the four wins to start the season.

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Casey said some of the downturn is the early reliance on Blake Griffin to create his own shot, en route to a 27.3 points per game average, which would top his career-best season by more than three points per game.

With Griffin post-ups continuing to be a focal point, Casey said assists should come off that going forward. But Griffin’s 4.3 assists per game is down from 6.2 in his 25-game stint with the Pistons last season after January’s trade from the Los Angeles Clippers.

“That’s one of the things we’re going to have to get to is trusting the pass, trusting the kick-outs, and then those guys out there sitting down and pulling the trigger,” Casey said. “Having the confidence that if you miss 15, shoot 15 more and having that mentality, and that rhythm is going to come. I don’t know when it’s going to be, but it’s going to come.”

Griffin’s playmaking also has taken the ball out of the hands of point guards Reggie Jackson and Ish Smith, who have also often shared the court.

Jackson is averaging 3.6 assists per game and Smith is getting 3.3. Their assists per 36 minute averages of 4.2 and 4.1, respectively, are the lowest of their combined 17 seasons in the league.

The Pistons 3-point mark of 32.3 percent is 26th out of 30 teams the league.