SANTA CLARA, Calif. (AP) -- NaVorro Bowman slowly made his way inside 49ers team headquarters on crutches Monday for a short visit before departing, one day after the All-Pro linebacker sustained a serious left knee injury in San Francisco's NFC championship loss at Seattle that could put his 2014 season in question.
Coach Jim Harbaugh said after Sunday's 23-17 season-ending loss to the Seahawks that Bowman is believed to have a torn anterior cruciate ligament in his left knee.
There was no word Monday on potential surgery, though linebackers coach Jim Leavitt expected to learn more later Monday.
Leavitt said he remains optimistic that Bowman will be playing when the 49ers open new Levi's Stadium next season.
"He's a warrior. He's going to push forward, there's no question," Leavitt said. "He's a special guy, tremendously talented, but he's got such a heart. He's been so good with me it's unbelievable. He's great young man. He'll be fine. We're going into a new stadium and he'll be ready to go when we start."
In addition, left guard Mike Iupati broke his left ankle in the loss. He says he doesn't know whether he will need surgery, but is scheduled to be further evaluated Tuesday.
"This is a bad-luck year," said Iupati, who missed four games with a left knee injury. "I'll probably be in a cast for a while. I'll be here rehabbing. It's day by day and wish for the best."
As the 49ers braced for Bowman's lengthy recovery, they were still dealing with the sting of another season that ended just short of the goal.
Safety Donte Whitner was irked at any Seattle fans involved with throwing popcorn and other debris on Bowman as he was carted off at CenturyLink Field.
"That's pure ignorance," said Whitner, who noted losing to the rival Seahawks "makes it a little worse 'cuz I wanted to send those fans home crying."
And how about the postgame comments by cornerback Richard Sherman calling 49ers wideout Michael Crabtree "mediocre" and "sorry" following his game-saving defensive play in the end zone during the waning moments?
"Pure ignorance, simple as that," Whitner said.
Added tight end Vernon Davis: "He talks a lot. Sometimes you just need to shut your mouth. You got the win. Be humble, be gracious and just accept it. ... Maybe he could learn from other people around the league that know how to be a true gentleman that show good sportsmanship."
For Bowman, this is a terrible ending to a career season in which he emerged as a Defensive Player of the Year candidate. In December, Bowman's three sacks, two interceptions, one returned for a touchdown, two forced fumbles and a fumble recovery were unmatched by any other player all season.
The 25-year-old Bowman, drafted out of Penn State in 2010 and signed to a five-year contract extension worth $45.25 million in November 2012, had 145 tackles, five sacks, two interceptions and four forced fumbles this season.
"He sacrificed his body for this team. He's our leader and arguably the best player that we have," rookie safety Eric Reid said. "To see him go down, it hurts. I'll be praying for him and wishing him a speedy recovery. ... He was surprisingly optimistic (on the plane). He looked like he was doing OK."
Harbaugh, Leavitt and the other coaches met with their players Monday morning, passing out paperwork on the offseason conditioning program before everybody packed their belongings and parted ways.
For many, especially players on defense, having the season end seeing Bowman go down made it that much tougher.
"I didn't talk to him, because there's nothing really that you can say to somebody that puts so much into it and they go out with an injury like that," Whitner said. "From playing up here and being on this high level to being dropped all the way to the bottom on an injury, it has to be devastating. So I don't really know what to say to him right now. I'll say something eventually."
Notes: LB Ahmad Brooks is scheduled to fly to Hawaii on Tuesday to join the NFC Pro Bowl team, though the 49ers didn't yet know whether other selections planned to attend or pull out of the game. ... C Jonathan Goodwin said he will listen to any offers this offseason but also might consider retirement. "Deep down I think I'm still willing, but what creates uncertainty for me is being a 35-year-old free agent, which in this time of the NFL can be tough," Goodwin said. ... Whitner and WR Anquan Boldin also are uncertain they will be back with the 49ers. Whitner said he would like to stay and that Harbaugh and GM Trent Baalke expressed they would like him to return. "Hopefully we can get something done," Whitner said. "This is a business. Sometimes players don't fit into what you want to do salary-cap wise."
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