The first running back taken in the 2002 draft, Green has shown slow but steady improvement during his rookie season. Stuck behind Jamel White throughout the first half of the campaign, Green emerged last week, running for 96 yards in a win at Cincinnati as White rested an injured shoulder.
With White sidelined again, Green carried 28 times and led an effective ground game that amassed 164 yards. He took some of the pressure off Tim Couch, who completed 12 of 21 passes for 182 yards and a score.
"We're really hitting on all cylinders right now," Couch said. "William means so much to this team right now with what he's doing. He gives us a chance to run our whole offense."
"When you go on the road, if you want to be any good, you have to run the ball and take the crowd out of the game to some extent," Browns Coach Butch Davis said. "It eats up yardage, but more importantly, it eats up time."
Meanwhile, New Orleans quarterback Aaron Brooks was afforded no such luxuries. Running back Deuce McAllister, who leads the NFL with six 100-yard rushing games, dressed but did not play due to an ankle injury. That left the ground game in the hands of untested James Fenderson, who had just 35 yards on seven carries and also fumbled.
"You take Deuce away, you're asking a lot of James and Curtis (Keaton) to take on a bigger role than they've had," Brooks said. "No doubt about it, we missed Deuce."
"Anytime you have one of the best players in the league out at the running back position, it's going to affect you," Saints wide receiver Jerome Pathon said. "Having said that, we still had a lot of plays out there we should have made.
Brooks was 23 of 40 for 318 yards. But he threw three interceptions, two coming near the Cleveland goal line, and also fumbled to squelch a scoring opportunity.
"(Brooks) didn't make good decisions in the red zone, especially when we knew we needed two scores and we could have settled for a field goal that time (late in the third quarter)," Saints Coach Jim Haslett said.
The Browns (6-5) became the first AFC North team to beat an NFC South team (1-7-1) and remained a half game behind Pittsburgh as they look for their first playoff berth since returning to the NFL.
As a junior at Boston College last season, Green gained 1,006 yards in six games on artificial turf. This was his first NFL game on the fake surface and his first 100-yard game.
"Yes, turf is home sweet home," Green said.
The Saints (7-4) have lost three of their last four games and slipped into third place heading into next week's showdown with division leader Tampa Bay.
"I told them we stunk, we were awful, and that's not us," Haslett said. "We had a lot of turnovers."
"You're going to have adversity at some point," Saints defensive lineman Norman Hand said. "Now that we have adversity, we need to see who is going to step up and make plays and get the job done."
Brooks and the Saints were particularly sloppy in the second quarter. After John Carney's 27-yard field goal in the first minute of the period pulled New Orleans within 7-6, Brooks drove the Saints inside the Browns' 15-yard line.
But the quarterback simply lost the ball while dropping back to pass and Courtney Brown fell on it at the 15.
Cleveland was forced to punt, but Michael Lewis fumbled the return and Andra Davis recovered at the New Orleans 36. Two plays later, receiver Dennis Northcutt -- lining up in the backfield -- took a handoff and raced to the end zone for a 14-6 lead with 3:50 before halftime.
Carney's 30-yard field goal appeared to make it 14-9, but the Saints took the points off the board when Cleveland's Kenard Lang was whistled for unsportsmanlike conduct.
An 11-yard run on a fake punt by Fred McAfee highlighted an 80-yard march capped by Fenderson's 17-yard touchdown run with 8:18 left in the third quarter. But the Saints squandered a chance to tie when the two-point conversion failed.
Couch answered with a 40-yard pass to Northcutt and Green raced 10 yards before Couch found Kevin Johnson with a 24-yard touchdown pass for a 21-12 lead with 4:44 to go.
"Now that William is running the ball the way he is, teams are bringing the safeties into the box and giving us a chance to get those big chunks down the field," Couch said.
Late in the period, Brooks again drove the Saints into the red zone. But after a wild scramble, he tried to force a pass into the end zone through double coverage and was intercepted by Earl Little.
"We just knew that things were going to be a little different for him because he didn't have Deuce," Little said. "At the same time we showed a coverage and would go back to a different coverage. Personally, I didn't think he could read that well, so we screwed him up a little bit. He didn't read coverages that well."
"The second one was just real bad for me," Brooks said. "Out of the three, that was the one I probably wanted back. I was throwing late in the middle across the field."
An interception by Fred Thomas set up Carney's 48-yard kick that cut the deficit to 21-15 with 10:14 remaining. But Couch engineered a 13-play drive that consumed nearly seven minutes and resulted in Phil Dawson's 28-yard kick that made it a nine-point game with 3:25 to play.
I thought William Green controlled that drive," Couch said. " He was just taking time off the clock. We converted a couple of passes in there, mixed it up very well."
Notable deaths of 2014 [PHOTOS]