Mario Williams would have had plenty of other options. The former first overall draft pick by the , Williams was the best defensive player available this year, the rare elite pass rusher to hit the open market in his prime. But the Bills made him their goal for free agency, not just to shore up an anemic pass rush but also to give a boost to a franchise and a fan base desperate to be relevant again after not making the playoffs in a dozen seasons.
So when free agency began Tuesday, the Bills were there with a private plane to whisk Williams to Buffalo, and then they would not let him leave.
He remained there for two nights — an unusually long visit for a free agent — while the Bills plied him with everything from tours of residential neighborhoods to conversations with the former Bills star Jim Kelly.
Finally, they overwhelmed him with an offer that no other team was prepared to approach — a six-year deal that guarantees Williams $50 million, the biggest guarantee ever given to a defensive player. It surpasses by nearly 20 percent the $42 million guarantee given to Julius Peppers by the Chicago Bears only two years ago and makes Williams the third player in N.F.L. history to be guaranteed $50 million, after quarterback Sam Bradford and receiver Calvin Johnson, who got his Wednesday.
On Thursday, Williams signed, becoming the biggest free-agent acquisition in Bills history and the biggest — so far — in free agency this season.
The Bills had been a long shot to land Williams, but now that they have him, the defense that had only 29 sacks last season — only two teams had fewer — should have one of the most dominant defensive lines in the game. Williams will join end Chris Kelsay and tackles Kyle Williams and Marcell Dareus in the 4-3 defense.
The signing also sends a signal for future free agents: Buffalo is not that bad. Just ask Williams.
“You hear so much about living here, until you actually get here and see what’s here and see the fans and everything this great city has to offer, even seeing my name on pizzas — it definitely got the message across,” Williams said when he was introduced at a news conference Thursday afternoon. “You don’t get many chances like this to be the guy who can help the team get across the hump. And that’s definitely what I’m here for.”
The Bills probably overpaid a bit for Williams, but Buffalo has not had a pass rusher like Williams since Bruce Smith, who left the team in 1999. Williams has had 53 sacks in six seasons, including five in five games before he tore a pectoral muscle that ended his 2011 season.
And the signing instantly energized a franchise that started 5-2 last season — igniting hopes that it, like the Detroit Lions, was about to begin a renaissance — before fading and finishing 6-10.
Buffalo receiver Stevie Johnson, who received his own extension this off-season, offered praise on his Twitter feed for the Bills executives who made the Williams deal.
“I Love it!” he wrote. “Welcome SuperMario!”
The Texans drafted Williams in 2006 instead of taking Reggie Bush in an effort to stop Peyton Manning when he was with the Indianapolis Colts. Now, the Texans may have to take on Manning again without Williams. Manning continued to mull his options Thursday, after spending about eight hours Wednesday meeting with coaches from the Tennessee Titans.
The Titans are making a big push to sign Manning. The owner Bud Adams told a Houston television station that he had offered to make Manning a Titan for life. And on Thursday, they may have helped their chances when they signed guard Steve Hutchinson, a former Pro Bowl selection who was also being sought by Seattle, the team that drafted him.