The team officially broke the news on Twitter, while Ian Rapoport of NFL.com provided the financial terms of the deal:
David, who was slated to become an unrestricted free agent in 2016, will receive a significant raise from the $738,418 base salary he's set to make in 2015 as part of his rookie contract, according to Spotrac.
The 2012 second-round pick out of Nebraska has quickly developed into one of the NFL's top linebackers. He was named a first-team All-Pro two seasons ago after recording seven sacks and five interceptions, and he has posted at least 145 tackles in consecutive campaigns.
Although David missed two games because of injury last season, he has started every NFL contest he has played in, and he has never racked up fewer than 139 tackles in a single year.
By virtue of that, NFL.com's Bucky Brooks recently tabbed him as one of the best tacklers in the entire league:
While David doesn't necessarily receive the credit he deserves from a league-wide perspective, the Bucs are well-aware of the type of player they have on their hands.
According to Jenna Laine of Sports Talk Florida, Tampa Bay made no effort to hide its appreciation for David during the lead-up to his contract extension:
General manager Jason Licht was particularly outspoken about David and what he means for Tampa's defense moving forward, per Roy Cummings of the Tampa Tribune.
"Lavonte is a model player, a cornerstone of this franchise," Licht said. "And it is our intention to make sure that he's a part of this organization for years to come."
While much of the focus is on the Bucs offense because of the arrival of rookie quarterback Jameis Winston and the continued development of wide receiver Mike Evans, the defense must continue to improve as well in order for Tampa Bay to become a contender in the wide-open NFC South.
The Buccaneers ranked 25th in points and yards allowed last season, but it would have been far worse without the services of their 25-year-old stud linebacker.
Tampa is starting to build a talented defense with linemen Gerald McCoy and George Johnson and cornerbacks Alterraun Verner and Johnthan Banks, but David is and will continue to be the cornerstone guy.
If he continues to produce at a rate similar to what he has shown to this point in his career, the Buccaneers will have a great deal on their hands.
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