Rice got hurt on a four-yard reception where he was tackled by nose guard Ahtyba Rubin and appeared to fall awkwardly.
Rice's status for next week's game against the Pittsburgh Steelers remains unclear, and he's schedule to undergo a magnetic resonance imaging exam today to get a formal diagnosis.
"We don't know right now," Ravens coach John Harbaugh said. "There's nothing ligament-wise that's a problem, so that's probably where it starts. So, that's the most important thing. Or, cartilage-wise, as far as we know. We don't know the extent for sure."
Rice wasn't made available for interviews after the game, but the team distributed quotes from the all-purpose back.
Rice didn't specify what happened to his knee, but seemed optimistic about his prospects of playing against the undefeated Steelers next week at Heinz Field.
"Right now, everything is standard," said Rice, who rushed for 80 yards on 15 carries before leaving the game. "I'll take some tests on Monday, but everything looks positive right now."
Rice, who had a 25-yard run against the Browns in the first quarter to set up a touchdown, gained over 2,000 yards from scrimmage last season.
Once he got hurt, Rice was on the bench and attended to by trainers and doctors.
Afterward, Rice was talking as if he'll play against the Steelers.
"They're playing good football and they're tough upfront," Rice said. "We're going to prepare hard this week and hopefully everything will be good to go."
In relief of Rice, former Pro Bowl runner Willis McGahee rushed for 29 yards on seven carries.
He expressed confidence that he can shoulder a full workload.
"I'm pretty sure Ray is going to be all right," McGahee said. "Whenever my number is called, I'll be ready."
Offensive tackle Michael Oher predicted that Rice will bounce back quickly from the knee injury.
"He's a tough kid and a tough guy," Oher said. "He's going to be fine."
LONG DAY: Rugged Browns running back Peyton Hillis ran roughshod over the Ravens' usually stout defense.
He rushed for 144 yards and a touchdown on 22 carries, gaining 48 yards on one run.
"Just one word: beast," Pro Bowl fullback Le'Ron McClain said. "He's downhill, north south. He's fun to watch. That's the game of football: big back getting downhill on the defense, wearing people down."
A former Arkansas standout acquired in a trade from the Denver Broncos that sent quarterback Brady Quinn to Denver, Hillis is the fourth runner to rush for 100 yards against the Ravens since last season as he joined Cedric Benson and Adrian Peterson.
"I'm not easily impressed, but I am," linebacker Terrell Suggs said. "I'm usually not easily impressed, but he impressed me. He's a good back, but we'll be ready for him next time around."
Hillis, a 6-foot-2, 250-pound powerhouse who played fullback, tight end, running back, wide receiver and returned punts and kickoffs for the Razorbacks, averaged 6.5 yards per carry.
Ravens nose guard Kelly Gregg compared the burly runner to former Tampa Bay Buccaneers bruiser Mike Alstott.
"We knew that he's a downhill back, but we were thinking they were going to run the other guys some more," outside linebacker Jarret Johnson said. "They just lined him up and pounded him downhill and popped a lot of runs. It was really disappointing to us."
Added Gregg: "He was laughing out there, having fun. He was running hard. He's tough."
Hillis replaced Jerome Harrison, who was scratched due to a thigh injury.
"I always have to believe in myself, that I can have a big game," Hillis said. "Throughout my past, no one ever gave me much of a shot to do anything individually."
Inside linebacker Dannell Ellerbe indicated that the Ravens didn't specifically game plan for Hillis.
"We knew he was a downhill guy and the other one was more speed," he said. "Hillis is straight power. I like the way he plays. He's always been good. He's a strong player."
All-Pro middle linebacker Ray Lewis had some rough moments against Hillis, but didn't seem concerned.
"Unless you don't play for us, you can panic," Lewis said. "But if you're been around here long enough, you come back to work and you go back to work, that's it."
OHER FLAGGED: Oher got into an altercation with Browns defensive end Robaire Smith in the fourth quarter, drawing an unnecessary roughness penalty.
Oher went after Smith after the defensive lineman shoved tight end Todd Heap after a false start.
"That's my teammate," Oher said. "You got to have your teammate's back.
"He was out of line with what he was doing a little bit. I could have controlled myself a little better. Just got to know better."
When asked if he threw a punch at Smith, Oher said he didn't remember.
He smiled when asked if he went looking for Smith after the game and said he didn't recall.
MASON FLAGGED: Wide receiver Derrick Mason was penalized for delay of game in the third quarter.
Clearly frustrated after an incomplete pass from Joe Flacco, Mason tossed the ball high into the air instead of handing it to an official.
Mason maintained his recent policy of not conducting interviews, declining a request for comment in the locker room.
Harbaugh had an elaborate explanation about Mason's actions.
"It wasn't out of frustration," he said. "That's the thing I saw. He and I looked at each other and he said, ‘Take me out for a play.' Then he said, ‘Coach, I'm good. I can't believe they threw the flag, but I have to know better than that.' It wasn't a frustration factor. What you've got to understand about NFL football players, they want to be the difference.
"They want to be the guy that wins the game. And they understand the ball is going to get spread around. I just think we have to understand how the rules are called, never put our team in jeopardy with a penalty and that's where the line is drawn. I need our guys to be smart enough to do that."
INJURY UPDATE: Defensive end Cory Redding left the game with a concussion and didn't return.
Defensive end Trevor Pryce twisted his leg, but returned to play without incident.
WILLIAMS RETURNS: Cornerback Cary Williams contributed one special-teams tackle in his first game since serving a two-game suspension for violating the league's personal conduct policy.
"It felt good to be back out there amongst my peers and working hard and things like that throughout the week," he said. "It feels good to come back and b e out there amongst the guys and play football, the game I love."
Williams said he's still working to shed some rust.
"It felt good to be back, but I'm not all the way there yet," he said. "I want to think fast on my toes. There were some situations where I thought I should have been better. It was a learning experience, and something I can grow on from this point on."
CODY DEACTIVATED: Rookie defensive tackle Terrence "Mount" Cody didn't play after practicing all week.
Late last month, Cody had arthroscopic surgery to repair a torn a meniscus in his left knee.
"It was real close," Cody said. "They came up to me and said, ‘We're going to sit you. You had a real good practice this week, but we just want to be safe and give you another week.'"
The second-round draft pick from Alabama is eager to play in his first NFL game.
"I was kind of upset, but, at the same time, it was the coach's decision," he said. "Can't fight the decision."
Harbaugh indicated that Cody isn't quite ready yet.
"It's two-fold," he said. I think his knee is not 100 percent. He certainly could've played. It's also, ‘Who do you put down?' We had some good players up. We'll just have to see next week where he's at. He's ready to play, though."
Cody said that he plans to play against the Steelers.
"I'm practicing and playing this week definitely," he said. "That's what I was told."
QUICK HITS: The Ravens also deactivated wide receiver Donte' Stallworth (broken foot), cornerback Prince Miller, linebacker Tavares Gooden (dislocated left shoulder), defensive tackles Arthur Jones and Lamar Divens, offensive tackle Jared Gaither (thoracic disc injury) and defensive end Paul Kruger (shoulder). … The Browns played without starting quarterback Jake Delhomme (high ankle sprain) as well as wide receiver Carlton Mitchell, Harrison, nose guard Shaun Rogers (hip, ankle), wide receiver Brian Robiskie (hamstring), offensive guard Shawn Lauvao, offensive lineman Steve Vallos and linebacker Marcus Benard. …
Playing in the nickel package primarily, Ellerbe recorded six tackles. "I felt like I did good out there," he said. "I had a couple of good tackles." … Mason, defensive tackle Haloti Ngata and punter Sam Koch were the Ravens' game captains. … Finksburg youngster Preston Ricks was named the Rookie of the Game.
Ravens notebook:Ray Rice sprains knee
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