The Miami Heat started Game 3 of their Eastern Conference Finals series against the Boston Celtics on the right foot, running out to a 21-point lead after the first quarter. The Heat led by as many as 26 points in the second quarter before that lead was trimmed down to 15 at halftime, and the rest of the game was them just trying to hold on without Jimmy Butler in the second half.

 

The Celtics managed to trim the deficit down to one at 93-92 late in the fourth quarter, but they couldn't get over the hump in a 109-103 loss. While players like Jaylen Brown, Marcus Smart, and Al Horford all turned out to be bright spots, there were some notable struggles that played a big role in the defeat. Now trailing 2-1 in the series, Boston will have to make the right adjustments and lessen its errors in Game 4 while also accounting for Bam Adebayo, who poured in 31 points in Game 3.

But before that, let's take a look at three Celtics players who had major roles in their Game 3 loss to the Heat.

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3 Celtics most to blame for Game 3 loss to Heat

3. Daniel Theis

The Celtics were hit with a tough blow when it was announced that Robert Williams would not play in Game 3 because of his ongoing knee problems. Ime Udoka went with Daniel Theis as the starter to replace Williams, and it didn't go well.

Boston got blitzed to start Saturday's game, with Theis looking unplayable. The Celtics were outscored by 19 points in Theis' first stint of the game, which lasted nearly eight minutes. He only played three more minutes the rest of the game.

Theis wound up with one point, three rebounds, one assist, and two turnovers in his nearly 11 minutes of action. He was a minus-13 in the box score, the second-worst mark on the team. Udoka turned to Grant Williams for 39 minutes, and he was more effective.

We'll see what Udoka has in store for Theis in Game 4. It would make sense to simply just start Grant Williams if Robert Williams can't play.

2. Derrick White

Derrick White didn't suit up in Game 2 because of the birth of his son. In his absence, both Marcus Smart and Payton Pritchard stepped up and scored 24 and 10 points, respectively, which helped Boston earn a dominant 127-102 victory.

White returned to the team in Game 3 but failed to make his presence felt in the 14 minutes of action that he saw on the floor. He ended up scoreless and finished with just two rebounds and an assist. The Celtics were outscored by two points in his 14 minutes.

Pritchard, meanwhile, only played 13 minutes. He made his lone 3-point attempt and handed out four assists. Boston outscored Miami by seven points in Pritchard's minutes.

Without a doubt, a higher level of production is needed from rotational players like White, particularly in a game where their main guy in Jayson Tatum is struggling. The veteran guard has to do better and bounce back in Game 4 if they want to keep up with their opponent for the remainder of the series, especially with Kyle Lowry now back in the fold for Miami.

1. Jayson Tatum

The missing link for the Celtics in Game 3 was none other than Jayson Tatum. He wasn't his usual self as he found himself in a shooting slump all game long. The three-time All-Star only scored 10 points on 3-of-14 shooting from the field. He also shot poorly from beyond the arc by making just 1-of-7 of his 3-point attempts.

Tatum rounded out the night with six rebounds and four assists in 40 minutes. Similar to Game 1 of the series, he also had many individual errors by turning the ball over six times. Boston turned the ball over 24 times in the game, leading to 33 Miami points.

Adding injury to insult, Tatum hurt his shoulder in the fourth quarter, though he did return and should be okay. Still, any type of injury for the Celtics' star player isn't good news.

Tatum now must bounce back in Game 4. He has to find his offensive rhythm early and also lessen his turnovers. Boston has been great at bouncing back after losses, so don't be surprised if Tatum puts forth one of his best games of the postseason on Monday.