The deal actually amounts, though, to a one-year term of service because of escalating cap figures and base salaries after the first year. Oakland is an aging franchise whose window of opportunity to win a Super Bowl is closing rapidly.
The Raiders won a war for Adams's services over the Ravens, Denver Broncos, Seattle Seahawks and the Cincinnati Bengals. The contract lasts for six years, but Adams won't last that long in Oakland because of accelerating contract years after his initial season in the Bay Area.
"I'm happy for Sam," Ravens coach Brian Billick said. "It's a great opportunity for him. The structure of the deal was clear-cut. That has been the catching point for us.
"It's just not prudent for us, with someone of Sam's stature and abilities, to do what amounts to a one-year year deal. That was the sticking point for us. We were committed since Day One to a more long-term reference point."
The Raiders' offer was reportedly significantly higher than the $1.5 million proposals that the Seahawks and Broncos dangled at the 330-pound former All-American at Texas A&M.
Baltimore was prepared to give Adams a signing bonus in the range of $2.5 to $3 million, but wanted to ink Adams to a long-term contract that wouldn't damage its already precarious salary cap budget.
"Unfortunately, he was more focused on wanting to have a one year deal to allow himself to get more," Billick said.
The Bengals' $3 million offer wasn't to Adams' taste, either.
Oakland becomes Adams' third NFL team after prior stints with the Seahawks and Ravens, whom he helped win a Vince Lombardi Trophy two seasons ago.
Adams is only 29, but has one of the quickest first steps of any defensive linemen in the game.
Billick said he couldn't speculate on what Baltimore might try to acquire now that the speculation surrounding Adams is over.
Broadcast and published reports in this market were conducted as if his arrival was a done deal, when, in fact, a pact was never solidified. A contract isn't completed until it's done.
That's a hard lesson Baltimore already learned this off-season when it failed to get offensive tackle Marcus Spears' signature on a contract after reaching an agreement in principle, with the blocker opting to return to the Kansas City Chiefs.
In Baltimore last season, Adams registered 51 tackles, 28 solos, two sacks, two pass deflections and one forced fumbles.
In 2000, Adams collected 69 tackles, two sacks, seven pass deflections and tied for the team lead with outside linebacker Jamie Sharper with five forced fumbles.
In 1997, Adams had seven sacks for the Seahawks.
While Adams has been a productive athlete, he's also prone to moodiness and being chronically overweight. Still, Adams' absence will have an impact on the Ravens' front seven.
The Ravens will try to make do with Kelly Gregg on the defensive line along with Tony Weaver, Michael McCrary, Marques Douglas and, possibly, Adalius Thomas, if he moves back to defensive end from outside linebacker.
"Yeah I am disappointed," Ravens Pro Bowl outside linebacker Peter Boulware said. "Sam was one of my good friends. I really believe we could have used Sam. "That's the nature of the NFL. Sam got the best deal and decided to take it."