Surgery couldn't have gone better! Received great news! Already started the recovery process!Thank you for all of your prayers as I heal up!— Derek Carr (@derekcarrqb) December 27, 2016
Carr's mother, Sheryl Joyner-Carr, also wrote on her Facebook page that her son was out of surgery in Los Angeles and is doing "EXCELLENT!" She thanked fans for their support and prayers.
The Raiders have given no timetable for how long Carr will be sidelined, but ESPN's Adam Schefter reported that the third-year quarterback is expected to be sidelined six to eight weeks.
A source told ESPN's Adam Caplan that if the Raiders were to advance to the Super Bowl, the possibility Carr could be ready in some capacity couldn't be ruled out.
But for now, Oakland (12-3) will head into the postseason relying on backup quarterback Matt McGloin.
The Raiders can clinch the AFC West title and a first-round bye with either a win at Denver on Sunday or a Kansas City loss in San Diego. If the Raiders lose and the Chiefs win, Oakland will open the playoffs at AFC South champion Houston on wild-card weekend.
"We're up for the challenge," Raiders running back Latavius Murray said. "I know Matt is. We're not going to change anything. We're going to go out and execute and do what we do."
They will just have to do it with McGloin under center, instead of Carr.
The Raiders believed enough in McGloin to place a second-round tender on him as a restricted free agent this past offseason, but he has had little time on the field since his rookie season in 2013.
While McGloin has thrown just 55 passes since making six starts late that year and Carr has been mentioned as a possible MVP candidate with 28 scoring passes, 3,933 yards passing and only six interceptions this season, the Raiders don't expect much to change with how their offense is run. Oakland players said both quarterbacks have similar approaches and work ethics, with the biggest difference being in their language.
"They're both great guys," backup quarterback Connor Cook said. "I would just say the only thing is McGloin probably swears a little bit more than Derek. That's the main difference."
According to Cook, McGloin has been "the same guy" since becoming the Raiders' starter.
"He's a grinder. He's tough," said Cook. "We believe in him and he believes in himself."
While Carr had been bred for the NFL ever since his brother, David, was the No. 1 overall pick by Houston in 2002, McGloin had to walk on at Penn State before becoming a starter in college, was undrafted in the NFL and had spent most of his four years as a backup.
McGloin uses those perceived slights as motivation to succeed where others thought he couldn't.
"It's almost like he lives for being that underdog, and that's what fuels him," said Oakland tight end Mychal Rivera, who played when McGloin started in 2013. "And it's brilliant. We're going to rally behind him."
McGloin steps into a much better situation this season than he did three years ago, when he replaced an injured Terrelle Pryor at quarterback for an Oakland team on the way to a 4-12 record. The Raiders now have one of the top offensive lines in the game, anchored by Pro Bowlers Donald Penn, Kelechi Osemele and center Rodney Hudson, and they have two top playmakers on the outside in wide receivers Amari Cooper and Michael Crabtree.
The running game behind Murray and rookies Jalen Richard and DeAndre Washington ranks fifth in the league at 124.3 yards per game, and it has been even more potent of late, with 157.3 yards per game over the past four contests.
Even the defense that struggled mightily early in the season has been much improved recently, behind the strong play of pass-rusher Khalil Mack.
But to have success, McGloin will need to make plays such as the 19-yard pass into coverage he engineered on a late third-down play to Cooper that helped Oakland run out the clock in Saturday's 33-25 win over the Indianapolis Colts.
"That was huge," said Raiders wide receiver Andre Holmes, who also played with McGloin in 2013. "He put the ball out there for Amari to go up and make a play on it. That's just showing how much confidence he has in Amari to make a play in a big-time moment. That's some of the things he did a lot when he was starting here a few years ago. He understands the abilities that his playmakers have."
Holmes said he has "full confidence" in McGloin.
"I just think he's always been prepared," Holmes said. "Him and Derek are always conversing with each other on and off the field, what they see, and now ... he's going to be the one out there making the plays."
ESPN's Paul Gutierrez and The Associated Press contributed to this report.