The trade, contingent on Williams passing a physical, addresses a significant need for the Bills by adding an experienced, proven starter to what had been a young group of receivers. In exchange, the Bills gave up a sixth-round draft pick.
At 6-foot-2 and 212 pounds, Williams has topped 900 yards receiving in two of his four seasons. That includes 2010, when he led NFL rookies with 65 catches, 964 yards and 11 touchdowns.
He comes to Buffalo with a hefty price tag a year after signing a six-year, $40 million contract. Injuries limited Williams to just six games last season, when he finished with 22 catches for 216 yards and two touchdowns.
Williams grew up in Buffalo, where he was a high school star. He then spent three seasons at Syracuse, where he played under current Bills coach Doug Marrone before abruptly quitting the team during his junior season.
In a statement released by the Bills announcing the trade, Marrone addressed the falling out at Syracuse by saying he feels that is now in the past.
''Today, Mike has an opportunity to get a fresh start to his career here in his hometown, and regain his form as a productive player in the National Football League,'' Marrone said. ''We feel Mike is a player who has the ability to help our team improve.''
Williams also missed the entire 2008 season after being suspended for violating the school's academic integrity policy.
With questions about his departure from Syracuse, Williams' stock dropped entering the 2010 draft. He was eventually selected in the fourth round, 101st overall, by the Buccaneers.
He made off-field headlines last month. On March 23, he was allegedly stabbed in the leg by his brother, Eric Baylor, who has since turned himself in to police.
Williams was treated and released from a hospital for a thigh wound. According to Hillsborough County Sheriff's office, Williams initially told deputies he and his brother were wrestling and the stabbing was accidental.
''At this time, we felt this was best for both sides, and we wish Mike well going forward,'' Buccaneers GM Jason Licht said of the trade.
Overall, Williams has 215 catches for 2,947 yards and 25 touchdowns in 54 games.
In Buffalo, Williams joins a receiving group that featured only one proven starter in Stevie Johnson.
Johnson's numbers plummeted in 2013 in part due to injuries, and he missed the final two games following the death of his mother. The Bills' passing attack struggled as a whole, finishing 29th in yards gained.
That was in part due to a series of knee injuries that limited rookie starting quarterback EJ Manuel to just 10 games.
Williams' addition provides the Bills an opportunity to address other needs in the draft next month; they own the ninth overall pick.
The Bills used two of their first four selections on receivers in last year's draft by choosing Robert Woods in the second round and speedster Marquise Goodwin in the third.
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