The Buffalo Bills today agreed to a new contract for wide receiver Stevie Johnson – a deal that will pay the four-year veteran a reported $36.25 million over five years, $19.5 million of it guaranteed.

That sets the bar for a free agent wide receiver market that boasts good depth and is led by Vincent Jackson, Marques Colston, Dwayne Bowe and Pierre Garcon. Johnson’s contract figures also give the Redskins – who have interest in Jackson, Garcon and Colston, according to sources – an idea of what it will cost for them to land a top wideout.

Buffalo Bills' receiver Stevie Johnson, left, is wrapped up by Washington Redskins' defensive back Josh Wilson (AP).

Jackson is four years older than Johnson, and Colston is three years older, but both have more impressive bodies of work. Colston has recorded thousand-yard seasons in five of his six NFL seasons, while Jackson has done so in three of the last four years.

Garcon, a four-year veteran like Johnson, comes off a season in which he recorded a career-high 947 yards and six touchdowns.

It appears that Jackson will not receive the franchise tag from San Diego for a second consecutive year. He made $11.4 million as the Chargers’ franchise player last year. Colston, meanwhile, drew a base salary of $3 million in 2011. Both figure to command contracts that will exceed Johnson’s. Garcon could wind up making a little less than Johnson.

Badly in need of a playmaker at receiver, and with more than $40 million in cap space to work with, the Redskins enter free agency prepared to pay handsomely to upgrade their receiving unit. We may learn exactly how much as early as March 13, when the signing period begins.

More Redskins’ free agent news:

Washington looks for an impact WR

Jenkins: Get Peyton

Reid: Pass on Peyton

Early Lead: Texans lock up Foster; Seahawks re-sign Lynch