WASHINGTON (AFP) — The Boston Celtics clinched the Eastern Conference championship on Monday with a 105-102 win over the Indiana Pacers, sweeping the series 4-0 and booking a spot in the National Basketball Association (NBA) Finals.

The Celtics will face the winner of the Western Conference Finals, where the Dallas Mavericks hold a 3-0 lead over the Minnesota Timberwolves ahead of Tuesday’s Game 4.

The Celtics win in Indianapolis was their seventh straight in the post-season but they left it late against a Pacers team again without injured star guard Tyrese Haliburton.

Jaylen Brown once again proved decisive.

He hit a step-through to level at 102-102 with 2:40 left in the fourth, then superbly rose to block Andrew Nembhard at the rim.

‘It’s been nothing but a grind, we haven’t skipped no steps all season.’

With 45 seconds remaining Brown found Derrick White in the corner who sank the three-point jumper that ultimately clinched the game — and the series.

Nembhard, who had 24 points, 10 assists and six rebounds for the Pacers, missed a three-pointer with 33 seconds left which would have tied the game.

Brown led Boston’s scoring with 29 points and Jayson Tatum had 26 points, 13 rebounds and eight assists.

The Celtics return to the finals two years after losing to the Golden State Warriors as they search for their first NBA title since 2008.

“It’s been nothing but a grind, we haven’t skipped no steps all season,” said Brown, named the Eastern Conference Finals Most Valuable Player after averaging almost 30 points through the series.

“We’ve got a bunch of great guys in this locker room, tough guys. Our coaching staff has been great, front office great and now we want to take the next step,” he added.

Boston have gone 12-2 throughout the post-season as they beat the Miami Heat, Cleveland Cavaliers and the Pacers to reach their 23rd NBA Finals in franchise history.

Celtics head coach Joe Mazzulla paid tribute to his team.

“Look at all the talent, look at the players that we have. It’s really all about them, they let us coach them. They allow us to push them, they listen to us and they set the temperature of the organization every single day,” he said.