DETROIT (Reuters) – The Cleveland Cavaliers completed their expected sweep of an overmatched Detroit Pistons in Sunday’s NBA playoff action, while a determined Chicago Bulls continued to take the fight to the Boston Celtics.

LeBron James scored 36 points to spark the Cavaliers to a 99-78 win over the Pistons, the top seeds easing into the Eastern Conference semi-finals with four straight victories in their best-of-seven series.

Seventh-seeded Chicago eked out a gritty win in double overtime, defeating defending NBA champions Boston 121-118 to knot their series at 2-2.

In other games, the Houston Rockets beat the Portland Trail Blazers 89-88 to take a 3-1 lead in their Western Conference series and Orlando pulled even with Philadelphia with an 84-81 win in Game Four of their Eastern Conference battle.

James also had 13 rebounds and eight assists in another dominant performance for Cleveland.

“That’s two games that he almost had a triple-double,” Cavaliers coach Mike Brown told reporters.

“He just does so much more than score for us.”

Detroit had made six consecutive trips to the Eastern Conference finals but the Pistons could not keep up with the Cavaliers, who also got 24 points from Mo Williams.

Cleveland will face either Miami or Atlanta in the next round.

In Chicago, John Salmons closed out the Celtics with two late free throws.

“This is the biggest game of our careers,” Ben Gordon, who sent the game into double overtime with a three-pointer and scored 22 points, told reporters.

“This says we never give up. We have a lot of fight on our side.”

Derrick Rose led the Bulls with 23 points, 11 rebounds and nine assists. Paul Pierce had 29 points for Boston and Ray Allen 28, including a three-pointer that, forced the first overtime.

Rajon Rondo added a triple-double — 25 points, 11 rebounds and 11 assists.

The teams return to Boston for Game Five tosday.

In Houston, Yao Ming delivered 21 points and 12 rebounds as Houston held off Portland, who pulled within one point on Rudy Fernandez’s three-pointer with 2.3 seconds to play.