Kiwanuka has been released by the Giants, NFL.com's Kimberly Jones reports.

The 32nd overall pick in the 2006 NFL Draft, Kiwanuka has 38.5 sacks over nine NFL seasons, all spent with Big Blue. He only had 2.5 sacks in 12 games in 2014, and while his knee should be healthy before training camp, he may have trouble landing a starting job.

The Giants placed Kiwanuka (knee) on injured reserve Tuesday, Field Yates of ESPN.com reports.

Kiwanuka will finish his season with 28 tackles (19 solo), 2.5 sacks, and two forced fumbles in 11 games. He has spent nine years with the Giants but could be a cap casualty during the offseason.

Kiwanuka (knee) has been downgraded to out for Sunday's game against the Jaguars, Art Stapleton of the Bergen Record reports.

Kiwanuka was only able to log two limited practices during the week due to knee issue, which simply wasn't enough to convince the coaching and training staffs of his health. Robert Ayers figures to step in to the starting role in his absence opposite Jason Pierre-Paul.

Giants DE Mathias Kiwanuka agreed to a $2.175 million pay cut.

Kiwanuka was mentioned as a possible cap casualty following the season. Instead, he's reducing his 2014 base salary from $4.375 million to $1.5 million and receives a $700,000 bonus in return. Kiwi can earn another $125,000 back via incentives. The move created $2.05 million in cap space for the Giants.

ESPN Giants blogger Dan Graziano believes DE Mathias Kiwanuka could be a cap casualty in the offseason.

Kiwi is in the second year of a four-year, $21.75 million deal. He's scheduled to earn a $4.375 million salary and count over $7 million against the 2014 cap. The Giants would save just $1.8 million in 2014 by cutting him. Kiwanuka has appeared in all 12 games this season, making six starts and recording 24 tackles and four sacks. The G-Men may want to re-sign LE Justin Tuck.

Mathias Kiwakuna will practice as the Giants' starting right end until Jason Pierre-Paul (back surgery) returns.

And JPP may not be back anytime soon; his Week 1 readiness is in question. After playing linebacker the past two seasons, Kiwi is loving his position re-switch. "To be able to slap your hand in the ground and not have to worry about going from one position to the other, it makes it more comfortable when you're out there," Kiwanuka said. "... It was a move I was looking forward to."

Justin Tuck said teammate Mathias Kiwanuka's heart is "set" on playing defensive end this season.

ESPN New York expects the Giants to move Mathias Kiwanuka back to defensive end full-time in 2013.

Kiwanuka struggled at linebacker last season, and may be able to rejuvenate his career at his natural position. With Osi Umenyiora ticketed for Atlanta, Kiwanuka could push LE Justin Tuck across from RE Jason Pierre-Paul. The Giants figure to upgrade their linebackers in the draft, but for now have Keith Rivers on the strong side, Jacquian Williams at weak side, and Mark Herzlich in the middle.

Giants SLB Mathias Kiwanuka has agreed to convert $1.5 million of his 2013 base salary into a signing bonus, freeing up cap space.

The $1.5 million was already a guaranteed portion of Kiwanuka's $2.95 million salary. So he's not losing any money. The simple restructure will give the G-Men a better chance to re-sign key free agents Martellus Bennett and Will Beatty. Kiwanuka, 30, managed just 37 tackles and three sacks as a 2012 role player.

Giants SLB Mathias Kiwanuka (groin) expects to be fine for Opening Day against the Cowboys.

"I'll be ready," Kiwanuka said after leaving Friday's preseason game against the Bears. The Giants and Cowboys are squaring off four days before anyone else in Week 1, but Kiwi's injury doesn't sound like a threat to his Wednesday Night Football status.

Giants SLB Mathias Kiwanuka was forced from Friday's preseason game against the Bears with a strained groin.

Kiwanuka has 12 days to get ready for Week 1, but groin injuries have a tendency to linger, so it's not a given he'll be ready for Opening Night against Dallas. Kiwanuka was having a big game before going down, abusing the Bears' shaky line and routinely pressuring Jay Cutler.

Giants SLB Mathias Kiwanuka's three-year extension is worth $16.5 million and includes $10.95 million guaranteed.

Kiwanuka received an $8.5 million signing bonus. His 2012 salary is guaranteed, as is over half of Kiwi's $2.95 million salary in 2013. Kiwanuka is assured of being a Giant through his age-30 season, and is under control through his age-32 campaign. The Kiwanuka deal can't be sitting well with Osi Umenyiora, who has been begging for a new contract several years running.

Giants signed SLB Mathias Kiwanuka to a three-year extension through 2015.

Without the new deal, Kiwanuka would have been entering a contract season in 2012. The 29-year-old pass rusher has settled in as largely a strong-side linebacker in the Giants' 3-4. Per Rotoworld offseason acquisition Mike Clay, Kiwi played 69 percent of his 2011 snaps at linebacker, 21 percent at end, and 8 percent as an interior defensive tackle. Kiwanuka finished with a career high 84 tackles, 3.5 of them good for sacks. He's now under contract through his age-32 season.

Giants DC Perry Fewell plans to use Mathias Kiwanuka as the team's starting strong-side linebacker on first and second downs.

"He's going to play linebacker this year," said LBs coach Jim Herrmann. "In our base package he's a linebacker. When we go to third down, all bets are off." Playing linebacker puts a cap on Kiwi's ceiling in IDP leagues, unless you can still use him at defensive end. He should have more tackles than most ends.

According to teammate Justin Tuck, free agent DE/OLB Mathias Kiwanuka has re-signed with the Giants.

There goes Osi Umenyiora's holdout leverage. Kiwi is a high-risk investment because of his neck injuries, but his versatility and pass-rushing ability also made him one of the most intriguing defenders on the market. The Giants may now be open to offers for Umenyiora.

ESPN New York's Ohm Youngmisuk has a "gut feeling" the Giants will re-sign free agent DE Mathias Kiwanuka.

It's believed the Giants are hoping to sign Kiwanuka to only a one-year deal as he comes off a serious neck injury. If that hasn't changed, Youngmisuk's gut feeling has a good chance of being incorrect. If Kiwanuka ultimately walks, 2010 first-round pick Jason Pierre-Paul will likely be forced into the Giants' starting lineup.

Giants GM Jerry Reese has reportedly considered offering free agent Mathias Kiwanuka a one-year offer to "re-establish his value."

Kiwi is expected to be "all systems go" for training camp, but the Giants want him to prove that his neck will withstand a 16-game season under a "low-risk, short-term deal." If that's the case, Reese figures to have plenty of competition for his services from teams offering incentive-laden deals. The Boston Herald has suggested the Patriots will be interested in Kiwi as an outside linebacker.

Free agent DE Mathias Kiwanuka (neck) is taking part in players-only workouts with the Giants this week.

Kiwanuka was granted medical clearance in February to resume his football career. It's nice to see him back on the field. Kiwi is a five-year veteran, so it's far from guaranteed that he'll be back with the G-Men for the 2011 season despite his second-rounder tender.

Giants extended a restricted free agent tender to DE Mathias Kiwanuka.

Kiwanuka is believed to have drawn the going rate of a second-round tender. The Giants are just going through the motions, however, believing that Kiwi will be unrestricted as a five-year veteran. Coming off a serious neck injury, Kiwi was recently given clearance to continue his football career.

Giants GM Jerry Reese issued a statement Saturday, announcing that free agent DE Mathias Kiwanuka (neck) has received medical clearance to continue his career.

Clarifying earlier comments that suggested Kiwanuka's neck injury was career threatening, Reese also said Kiwi is "fully committed to returning to football." Kiwanuka is a five-year NFL veteran, so the Giants could attempt to keep him with a restricted free agent tender. He's not going to get a long-term extension considering his injury and the Giants' line depth.