Cade Cunningham Detroit Pistons Boston Celtics
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Earlier this week, our own Colin Ward-Henninger put the Boston Celtics at No. 1 in his latest CBS Sports NBA Power Rankings. On Friday night, the Celtics backed it up by taking down the Detroit Pistons, 114-103, to extend their winning streak to five games. 

Jayson Tatum led the way, continuing his personal hot streak with 31 points, eight rebounds and eight assists, while Jaylen Brown and Marcus Smart combined for 42 points, 11 rebounds and nine assists. But as has been the case so often over the last few weeks, it was the Celtics' defense that made the difference. 

The feisty Pistons, who beat the Celtics just before the All-Star break and had won six of their last nine games heading into Friday's contest, trailed by just two entering the fourth quarter. At that point they were shooting 48.5 percent from the field and Cade Cunningham was generating plenty of good looks with his playmaking. That success would not extend to the fourth quarter.

With Cunningham sitting to begin the period, the Celtics ramped up the pressure and forced turnovers on three of the Pistons' first four possessions. After converting all of them into layups on the other end, the Celtics quickly built a nine-point advantage and never looked back. Even when Cunningham came back into the game, the Pistons couldn't get anything going. The Celtics' ability to switch and throw multiple looks at the rookie eventually wore him down. 

Here, Brown goes over the screen, so Cunningham tries to drive into the paint, but Robert Williams III uses his long arms to knock the ball away. 

Later on, Smart picks up Cunningham full court and makes him turn his back to the basket. After a screen, Grant Williams switches onto Cunningham and is able to bump him off his path to the rim and force a tough runner that doesn't go. 

These were just a few examples of how the Celtics made things difficult on the Pistons in the fourth. So much so that the Pistons nearly went the entire quarter without making a field goal. Only in the closing seconds, after the Celtics had largely stopped trying, were the Pistons able to get a few buckets from Saddiq Bey and Luka Garza

Even so, the Celtics held the Pistons to 2-of-15 from the field in the fourth quarter. Per ESPN Stats and Info, that was tied for the fewest made field goals in a quarter by any team this season. Stretches like that are why the Celtics have the best defense in the league (105.6 defensive rating). 

With their win over the Pistons, the Celtics have now won five games in a row and 18 of their last 21. All of a sudden they are just percentage points behind the Chicago Bulls for fourth place in the Eastern Conference, and 1.5 games behind the Milwaukee Bucks for second. If they keep defending like they did against the Pistons, they're going to be a serious problem in the playoffs.