Celtics exposed Luka Doncic's defensive flaws in Game 3

Doncic, battling a thoracic contusion suffered in Game 1 and a sprained right knee that has been lingering for most of the season, has struggled with defense throughout the playoffs. Injuries and shouldering the offensive burden justified Doncic's breaks on defense during Games 1 and 2 in Boston. 

In the first two games, Kyrie Irving struggled, scoring 12 and 16 points respectively, with a combined shooting performance of 13-for-37 (35.1 percent) from the field and 0-for-8 from beyond the arc. Doncic was the only Mavericks player to make more than one three-pointer in both games.

However, Game 3 marked a significant shift. Irving erupted for 20 points in the first half and finished with 35 points on 13-of-28 shooting (46.4 percent) and 4-of-6 (66.7 percent) from three-point range. In contrast, Doncic had an inefficient night, shooting 11-of-27 (40.7 percent) and 1-of-7 (14.3 percent) from behind the arc. 

Instead of ramping up his defensive efforts, Doncic continued to exhibit lackluster defense. He picked up two unnecessary fouls in the closing minutes, eventually fouling out while visibly frustrated. 

The final foul was an attempted charge that turned into a block on Jaylen Brown in the open floor. Doncic immediately yelled at the bench to challenge the clear block call, showcasing his exasperation.

He has struggled defensively this postseason.

It's ironic that Doncic, who reiterated in February on the podcast "The Old Man & The Three" that it’s easier to score in the NBA, is now being targeted defensively in the most crucial series of his career. 

While his offensive load and injuries offer some justification for his defensive lapses, the Celtics have expertly exploited those weaknesses.

By attacking Doncic, the Celtics have disrupted his rhythm and forced the Mavericks to compensate defensively, resulting in open looks for Boston’s shooters.

Doncic’s defensive struggles have become a focal point, and he must respond; otherwise, the Celtics seem poised to complete the sweep and secure their 18th championship, breaking a tie with the Los Angeles Lakers for the most titles in NBA history.

Game 4 will reveal Doncic's true character: will the franchise player tighten up defensively, or will he allow Boston to continue exploiting one of the Mavericks’ most significant weaknesses?