CHICAGO -- As they began to pull away and inch closer to advancing in the Eastern Conference playoffs, the Boston Celtics began to quietly celebrate Friday night.

And yet, despite playing with a comfortable lead, the realized they couldn't coast and inevitable as the final result seemed, the Celtics realized they couldn't allow the Chicago Bulls any hope of extending their season.

As slow as the series had started with back-to-back losses, the Celtics knew it was time to finish what they had started over the past four games.

Avery Bradley scored 23 points and all five Boston starters reached double figures as the Celtics blew out the Bulls 105-83 in Game 6.

The Celtics advance to face the Washington Wizards beginning Sunday in Boston. The Wizards eliminated the Atlanta Hawks with a 115-99 victory Friday night.

"(After the first two games), the team wasn't right," Celtics center Al Horford said. "But after that second game going into third, I thought we were in a better place and that helped us get over the hump."

And once the Celtics cleared an emotional hurdle that included star guard Isaiah Thomas dealing with the death of his sister in a car accident, they never looked back.

"I said this a couple of times -- bigger things than basketball happen and that takes precedence," Boston coach Brad Stevens said. "I was really proud of our guys how they treated each other and how they stuck together."

The Celtics did so in Game 6 when a quick start and a balanced scoring attack that included 16 points from Gerald Green and 12 apiece from Jae Crowder, Thomas and Horford was enough to do in the Bulls.

The Celtics broke the game open early in the third quarter. Boston started the second half on a 10-2 scoring run to build a 64-43 lead. Green capped the run with a 3-point field goal as the Celtics, who led by as many as 30 points, pulled away.

As Boston picked up speed, the Bulls ran out of gas.

Jimmy Butler, hobbled by knee soreness, led Chicago with 23 points. Robin Lopez also scored 10 points for the Bulls, who dropped the final four games of the best-of-seven series after grabbing a 2-0 lead with a pair of lopsided victories in Boston.

But after losing point guard Rajon Rondo to a fractured thumb after Game 2, the Bulls weren't the same.

"We got off to poor starts in pretty much every game after the first two," Bulls coach Fred Hoiberg said. " ... Obviously, when you get off to a poor start, you're expending a lot of energy."

Things just got worse as the season went on culminating on Friday night when boos broke out across the United Center and chants of "Fire Hoiberg" could be heard as the Bulls continued to struggle.

Dwyane Wade appeared to aggravate an elbow injury he sustained late in the regular season. The veteran struggled throughout the night, hitting on only 1 of 10 from the field. Isaiah Canaan scored nine points, Michael Carter-Williams added eight points off the bench and Paul Zipser had seven.

It all added up the Celtics closing out the Bulls in dominant fashion.

"They played like the (No.) 1 seed," Butler said of the Celtics. "When they do that, they're really hard to guard, they're a really good team."

Now, after advancing past the first round of the playoffs for the first time in the Stevens' tenure as coach, the Celtics will look to take another step when they face the Wizards.

Winning four straight games to close out the Bulls certainly built some momentum after Boston struggled to find their footing.

"The sky is the limit for this team," Bradley said. "Anything can happen as long as we continue to stay positive and play as hard as we can."

NOTES: Celtics G Isaiah Thomas was scheduled to leave for Seattle after Friday's game for his sister's funeral, which will be held Saturday. Thomas' sister, Chyna, was killed in an automobile accident earlier this month. Celtics coach Brad Stevens would not comment on which members of the team would be traveling to the funeral besides Thomas. ... Bulls F Jimmy Butler played 31 minutes despite dealing with knee soreness. Asked if Butler had taken any medication for the soreness, coach Fred Hoiberg said he did not know. "He's obviously got some soreness, but Jimmy's going to fight through it," Hoiberg said before Friday's game. "He's a warrior, he's a guy that is as well-conditioned as anyone in this league and he's going to go out and give everything that he has." ... G Rajon Rondo (thumb) and G Cameron Payne were inactive for the Bulls.