The Boston Celtics and the Dallas Mavericks have reached the NBA Eastern and Western Conference Finals, respectively, after both teams secured a big win in Game 7 of the Conference semifinals on Sunday.

The Celtics beat the reigning champions, Milwaukee Bucks, 109-81 at TD Garden in Boston after the whole team drained a new franchise record 22 triples. Seven of these 3-pointers were made by Grant Williams, who also scored game-high 27 points. When he shot to kill from outside, the Bucks' defensive arrangement of having Brook Lopez, their best rim protector, guard him failed.

Jayson Tatum, Jaylen Brown and Payton Pritchard combined 11-of-20 from downtown as well. Instead of challenging the "Fort Knox" set up by the Bucks in the paint directly, Tatum grew hot quickly behind the arc by shooting 4-for-4 from the field in the first half. Then in the second half, Tatum took advantage of his shooting threat from outside to force Giannis Antetokounmpo to step out before moving the ball quickly to punch the Bucks on the weak side. Though he only had six points in the third and fourth quarters, Tatum delivered six assists during this period.

The Celtics only led by five points (48-43) in the first half but launched a 61-38 run in the second half. The team's lethal 3-point shooting aside, their defense that separated Antetokounmpo from the rest of the Bucks also played a key role in Sunday's victory.

Antetokounmpo dropped 25 points, 20 rebounds and nine assists for the Bucks in Game 7. He remained unstoppable in the first quarter with 10+8+6, during which the team made three of the only four 3-pointers they made for the game. As the Bucks hit 1-of-23 from downtown, encouraging the Celtics to further close in on defense.

Antetokounmpo could still force his way toward the rim in the second quarter, but as his strength was running out fast from the third quarter as he had to both tussle with the "human great wall" set by Williams, Al Horford and Marcus Smart on offense and sweep the floor to race with the Celtics' ball movement on defense.

While the Bucks shot 12-of-31 in the middle range and 4-for-33 at the 3-point line, they missed nothing but Khris Middleton, who was absent from the series because of a medial collateral ligament sprain.

The Celtics will meet the Miami Heat in the East Finals, which begins in Game 1 at FTX Arena in Miami on May 17.

Compared with its East counterpart, Game 7 of the West semifinals was much more unbelievable in both the process and result. The Mavericks smashed the Phoenix Suns 123-90 at Footprint Center. They could have set a new record for the largest margin of victory in a Game 7 if it weren't for the points scored by the Suns' reserve players in the garbage time of the final quarter.

Both the Mavericks and the Suns couldn't be more familiar with each other as the series came this far. The Suns wanted to make Luka Doncic work alone instead of getting as many of his teammates as possible involved in the offense. The Mavericks tried to get the ball out of Devin Booker's hands to force the rest of the team to carry the offensive duties.

The Suns' defensive scheme failed. After Doncic scored 12 points, eight rebounds and three assists in the first quarter, Spencer Dinwiddie took over the offensive leadership role from him with a dominant performance. He scored 21 of his 30 points in the first half, during which he drained four triples. No matter who was guarding Dinwiddie, he always found a way to make the shots.

When Doncic came back in the second quarter, he contributed another 15 points for the Mavericks to score 27 in total, the same as the whole team of the Suns got in the first half. Chris Paul, Booker and Deandre Ayton combined 1-of-15 from the floor for the Suns in the first and second quarters. Ayton was the only one of the three to make a field goal (FG). Meanwhile, the rest of the team failed to take over the offensive responsibilities.

Both Doncic and Dinwiddie began to cool down in the third quarter, but Jalen Brunson made sure the Suns' nightmare continued with 24 points in the second half. There's one thing in common behind the incredible offensive performances of him, Doncic and Dinwiddie: they all targeted at Paul.

Everybody on the Suns must be sad at the lost Game 7 and the series, no one is likely to be in more pain than Paul. For Sunday's game, he became the wink link of the team on the defensive front; in general, this was the fifth time for Paul to blow a 2-0 lead in the playoffs and his fifth consecutive loss in Game 7s.

As a top 10 point guard in NBA history, Paul still doesn't have a ring. If the Suns make this far next season, he will turn 38 years old and likely to be slower and less endurable by then. If it makes any comfort, the Mavericks' head coach Jason Kidd, who was also an iconic point guard when he was a player, won his only title when he was 38.

Kidd won that ring in 2011 together with Dirk Nowitzki, who was sitting on the sideline during Sunday's game.

Of course, it's unfair to blame a veteran for everything. As the Suns' ace, Booker only took 14 attempts in Sunday's game and he missed 11 of them. Being double-teamed couldn’t be his excuse, especially with his shooting skill in the middle range. As for Ayton, he should have been the team's biggest advantage on offense. Instead, he only made two FGs in less than 18 minutes in a series decider like this. His underperformance basically blew away the maximum extension he wanted.

The Mavericks will play against the Golden State Warriors in the West Finals from Game 1 at Chase Center on May 18.