The Milwaukee Bucks came into Boston and have beaten the Celtics twice in convincing fashion to take a commanding 3-1 series lead.
Giannis Antetokounmpo finished Game 4 with 39 points and 16 rebounds on 68% shooting from the field. George Hill came off the bench and made an impact for the second game in a row with 15 points and five assists in the win.
Kyrie Irving finished with a team-high 23 points, 10 assists and six rebounds but shot poorly from the field for the third straight game.
Here are three takeaways from the Bucks Game 4 win:
Poor Celtics 3-point shooting
The Celtics didn't depend on the 3-point shot this season but it was a good barometer as to how they were playing. They finished the season shooting 36.5% from 3-point range, good for seventh in the league. In wins, they shot 39% from long range.
Coming into Game 4, Boston led the playoffs at 40% from three and they had been shooting the long ball at a high clip in the second round so far against the Bucks.
However, the triple wasn't falling for the Celtics in Game 4, finishing the game shooting a dismal 20.6%.
Boston shot under 25% from the perimeter six times this season, all of them were loses. Again, the Celtics aren't depended on the three but it's hard to overcome a bad shooting night from the floor, especially one as bad as Boston had in Game 4.
Bucks' Paint Points
The Celtics did an incredible job of keeping Giannis and the Bucks out of the paint in Game 1. Since then, they've been unable to stop Milwaukee from pounding them inside.
The Bucks outscored the Celtics 52-24 in the paint in Game 3 - in Game 4 it was 54-40 Milwaukee.
No one scored more in the paint this season than Giannis Antetokounmpo at 17.5 points per game, and he did it efficiently at 74%.
Boston was in the top five in paint defence, only allowing 37.1 points per game in the restricted area.
So far the Bucks have imposed their will on Boston since Game 1. The Celtics have no choice now, they have to show more fight and protect their rim or this series is over.
4-for-18, 8-for-22, 7-for-22 - those are the shooting numbers for Kyrie Irving in his last three games.
A quick glance at his stat line would leave you to believe Irving is doing enough to give the Celtics a chance to win, but the reality is he isn't.
It's not just about the lack of efficiency, which can't be understated from a superstar the calibre of Irving, but his lack of impact can't be overstated.
In Game 4, the Celtics were desperate for someone to put the team on their back and put them in a position to win - that person should be Irving, but when the time came to show up for his team, he failed to rise to the occasion.
Game 5 and every game from here on out is do-or-die for the Celtics. The only saving grace for Boston fans is this: Kyrie Irving has been in this position before, down 3-1 in a series with much higher stakes and was able to pull off the comeback.