The star receiver, Tom Brady's favourite target, is leaving New England and heading to Denver, where he'll join Peyton Manning and the Broncos.
Also getting new deals were Reggie Bush in Detroit, Dashon Goldson in Tampa Bay, and even Ray Lewis — with ESPN.
Day 2 of the NFL's free agency frenzy was highlighted by Welker grabbing a two-year deal with the Broncos, who had the AFC's best regular-season record last year. He gives Manning one of the steadiest targets the four-time league MVP ever has had.
"When you look at Wes in the middle of the field, you can't cover him," Broncos boss John Elway said. "He does such a tremendous job of getting open, finding seams in zones, beating man-to-man coverage. So, he'll be a huge asset for us inside."
The best slot receiver in the league, Welker caught 118 passes for 1,354 yards and six TDs last season. That the Broncos are signing a top player away from New England certainly didn't hurt, either.
"Anytime you can take a player from a team you have to compete against, it helps, especially the calibre of Wes Welker," Elway said. "New England is there year in and year out and that's a team we have to beat to get where we want to get."
Denver also came to terms on a two-year deal with defensive tackle Terrance Knighton, formerly of Jacksonville, and a one-year contract with linebacker Stewart Bradley, who played with the Cardinals the past two seasons. Later in the evening, the team added cornerback Dominique Rodgers-Cromartie with a one-year deal.
Bush agreed to a four-year deal and could fill a huge hole at running back. The Lions haven't been able to count on 2010 first-round draft pick Jahvid Best, whose career is in doubt because of concussion issues.
"It's a running back's dream," Bush said. "One of the reasons I wanted to come here is to be able to bring a balanced attack."
Bush adds to a strong offence led by record-setting All-Pro receiver Calvin Johnson. The second overall pick in 2006 by New Orleans, Bush rushed for 986 yards for Miami last season after gaining 1,086 yards in 2011, his first year with the Dolphins.
"The thing that was important to us was not just the talent of Reggie Bush, but also the way those talents complemented the other players we have on offence," coach Jim Schwartz said. "That was really the basis of our interest in Reggie."
The Lions also landed safety Glover Quin and defensive end Jason Jones and retained cornerback Chris Houston.
All-Pro safety Goldson gets a five-year contract worth $41.25 million. He receives $8.25 million per year and $22 million in guaranteed money. He spent the past two seasons on one-year contracts with the 49ers, including last year with the franchise tag for $6.2 million.
"Hard work really pays off. I remember signing up to play football, hiding it from my mom," as a youngster growing up in Harbor City, Calif., Goldson said. "My journey, I wouldn't say it was rough, but it was a little rocky."
Free agent defensive back Charles Woodson had a meeting with the NFC champion Niners in the Bay Area on Wednesday, according to his agent, Carl Poston.
Also Wednesday, former Kansas City Chiefs defensive end Glenn Dorsey signed a two-year contract after meeting with the Niners. The deal could pay Dorsey up to $7 million with incentives, a person with knowledge of the contract told The Associated Press. The person spoke on condition of anonymity because terms weren't announced.
One day after signing five players to contracts, Pro Bowl safety LaRon Landry became the Indianapolis Colts' newest addition by signing a four-year contract with Indy late Wednesday night.
"We're ecstatic about this signing," general manager Ryan Grigson said in a statement issued by the team. "We feel LaRon is an absolute game-changer and a true impact player. We're talking about a 220-pound safety that runs 4.3 (in the 40-yard dash) and plays to that speed. His approach to the game and his style of play are lights out and embody the culture we're building on the defence and this team in general."
Last season, with the New York Jets, he was selected to the AFC's Pro Bowl team after recording a career-high 113 tackles, matching his career-high with two interceptions and forcing four fumbles.
Cleveland remained active, agreeing to terms with linebacker Quentin Groves and tackle Desmond Bryant to further bolster a defence that added Ravens linebacker Paul Kruger hours after free agency began.
"With the additions of Paul and Desmond, we believe that we have significantly improved our defence overall, particularly our front seven," Browns CEO Joe Banner said.
Kruger is one of many Super Bowl winners to leave the Ravens, including hard-hitting safety Bernard Pollard, who was released Wednesday. The biggest loss for Baltimore was an expected departure: Lewis announced in early January that he was ending his 17-year career. Then he led the Ravens to the championship.
On Wednesday, he joined ESPN as a studio analyst — an intense one, no doubt.
"I'm ready to bring the same level of passion to this next phase of my life as I brought to the field during my years as a player," Lewis said.
Baltimore signed defensive lineman Chris Canty, offensive lineman Ramon Harewood and running back Damien Berry.
Kansas City added cornerback Dunta Robinson, receiver Donnie Avery and offensive lineman Bryan Mattison to the three free agents it signed the previous day when the marketplace opened.
The Chiefs, who have the No. 1 pick in next month's draft after a 2-14 season, agreed to deals with tight end Anthony Fasano, defensive tackle Mike DeVito, and quarterback Chase Daniel on Tuesday, when they also finalized the trade with San Francisco for starting QB Alex Smith.
After hiring Andy Reid as coach and John Dorsey as general manager, the Chiefs signed wide receiver Dwayne Bowe and punter Dustin Colquitt to long-term deals and franchised left tackle Branden Albert.
—Chicago released tight end Kellen Davis and also terminated the contract of tight end Matt Spaeth after signing Martellus Bennett away from the Giants on Tuesday to replace him.
—The Giants signed 11-year veteran place kicker Josh Brown, who joins former Cowboys kicker David Buehler on the roster and apparently indicating free agent Lawrence Tynes won't be back. Tynes has made winning field goals in two NFC championship games in overtime and the Giants went on to win the Super Bowl in those seasons.
—Pittsburgh found its backup to QB Ben Roethlisberger in a Steel City native, Bruce Gradkowski. The 30-year-old Gradkowski is 6-14 as a starter with Oakland, Cleveland and Tampa Bay. He spent the 2011-12 seasons with the Cincinnati Bengals, appearing in five games.
Pittsburgh also released oft-injured offensive lineman Willie Colon.
—Arizona, in dire need of help in the backfield, agreed on a one-year contract with former Steelers starter Rashard Mendenhall. For three of his seasons, Mendenhall's offensive co-ordinator was new Cardinals coach Bruce Arians.
The Cardinals also cut free safety Kerry Rhodes, a move that cleared $6 million in salary cap space, and added cornerback Jerraud Powers, safety Yeremiah Bell, linebacker Lorenzo Alexander and quarterback Drew Stanton.
—Jacksonville released receiver Laurent Robinson, the latest high-priced player let go as part of the team's rebuilding project. Robinson signed a five-year, $32.5 million free agent-contract last season before missing considerable time with concussions.
"It's unfortunate, but it's part of the business," Robinson said. "Got to keep your head up and keep moving. Can't ever be surprised in this league."
—Tennessee agreed to terms on a multi-year deal with fullback Quinn Johnson, who has been one of Chris Johnson's lead blockers with the Titans.
—Buffalo addressed a need at linebacker by signing seven-year veteran Manny Lawson. The Bills are switching from a 4-3 alignment to a 3-4 under new co-ordinator Mike Pettine.
—Miami already had signed linebacker Dannell Ellerbe and added to that unit Wednesday by giving Philip Wheeler a five-year contract, worth $26 million, half of that guaranteed. He spent his first four NFL seasons with the Indianapolis Colts and played last season for the Raiders, where he had career highs of 109 tackles and three sacks.
The Dolphins released linebackers Karlos Dansby and Kevin Burnett.
—Minnesota re-signed LB Erin Henderson and WR Jerome Simpson, while Washington did the same with DE Kedric Golston.
—New Orleans re-signed long snapper Justin Drescher to a four-year contract.
—The New York Jets re-signed fullback Lex Hilliard to a one-year contract, according to a person with knowledge of the situation. The person spoke to the AP on condition of anonymity because the team had not yet announced the move. Hilliard was signed in the middle of last season to replace John Conner.
—The Dallas Cowboys are releasing veteran defensive tackle Marcus Spears, with the move designated for June 1, when it will save the Cowboys $2 million against the salary cap. Spears, who turned 30 last week, was the second of two first-round picks after DeMarcus Ware in 2005.
—Seattle and defensive end Cliff Avril reached agreement on a deal that addresses one of Seattle's big off-season concerns, according to a person with knowledge of the situation. The agreement was still pending a physical.