Steven Jackson a Falcon

THE ATLANTA Falcons replaced Michael Turner with another proven, productive running back.

Steven Jackson, the top running back in free agency, agreed to a 3-year, $12 million deal with the Falcons on Thursday.

Also getting new deals were backup quarterback Matt Cassel in Minnesota and cornerback Keenan Lewis in New Orleans. The New York Giants signed defensive backs Ryan Mundy and Aaron Ross.

And the Houston Texans were rolling out the red carpet to make their pitch to safety Ed Reed.

Day 3 of the NFL's free agency frenzy was highlighted by Jackson, 30, moving on from St. Louis after his eighth straight 1,000-yard season.

"I think this is a very big signing for us," Falcons general manager Thomas Dimitroff said. "It continues to bolster our offensive firepower. It gives us not only strength, power in running ability but also the versatility to catch out of the backfield, which is a very important part of this offense."

Jackson would have earned $7 million with the Rams in 2013 before he opted out of his contract to become a free agent. His 10,135 yards rushing for his career are the most of any active player.

The Falcons released Turner, defensive end John Abraham and cornerback Dunta Robinson on March 1. Turner had 800 yards rushing last season, his low total in his five seasons in Atlanta.

Jackson averaged 4.1 yards per carry with the Rams and gives Falcons QB Matt Ryan another receiver. Jackson had at least 38 catches in each of his last eight seasons in St. Louis.

"We're hoping he has his best years ahead of him, there's no question about that," Dimitroff said. "We think he still has much fuel in the tank and I know that he believes that."

The Patriots moved quickly to replace new Bronco Wes Welker, luring receiver Danny Amendola on a deal that would reportedly pay him $31 million over 5 years.

Amendola posted a message on Twitter saying, "Blessed. Thankful. Excited to get to work. Go Pats." Rams coach Jeff Fisher also said Amendola had signed with the Patriots. The Patriots confirmed the deal later Thursday.

Amendola, 27, is a 5-11, 188-pound former rookie free agent from Texas Tech - the same school as Welker. After signing with the Rams in 2009, Amendola led the NFL with 66 kickoff returns, 1,618 kickoff return yards and 1,978 total return yards.

The following season, he led the NFL with 2,364 all-purpose yards, catching 85 passes for 689 yards and three touchdowns. Amendola has struggled to stay healthy, playing in 16 games only once.

Also Thursday, the Patriots announced the signing of running back Leon Washington, who has played seven seasons with the Jets and Seattle.

Washington, 30, shares the NFL record of eight career kickoff returns for touchdowns. He was selected to the Pro Bowl in 2008 and 2012.

The Vikings grabbed Cassel shortly after the Kansas City Chiefs let him go, a source told the AP. It was a busy day for the Vikings, who also were hosting receiver Greg Jennings for a visit.

Cassel spent the past 4 years in Kansas City, making the Pro Bowl in 2010 after throwing for 27 touchdowns and just seven interceptions. But he has struggled the past 2 years, with 16 TDs and 21 interceptions. He will replace Joe Webb as Christian Ponder's backup.

Also Thursday:

* Arizona agreed to a 3-year contract with inside linebacker Jasper Brinkley, who played for Minnesota the last 4 years.

* Tampa Bay signed linebacker Jonathan Casillas and receiver Kevin Ogletree.

Detroit offensive lineman Jeff Backus announced his retirement after 12 seasons.