ALAMEDA, Calif. — Richard Seymour ended his five-day sit out and joined the Oakland Raiders yesterday, saying he was initially "blindsided" by the trade from the New England Patriots.

"Since I got the call that I was being traded, my life's really been a whirlwind," Seymour said at a news conference at the Raiders facilities. "I've really been blindsided by the events that took place. I didn't expect it. I didn't understand what was going on. So it's like when something happens, when you're blindsided, you have to step back and realize what situation you're in."

Seymour was acquired last Sunday for a 2011 first-round pick but did not immediately report to the Raiders, raising speculation he did not want to join Oakland.

In his first public comments since the deal, Seymour told the Boston Herald yesterday that he was taken aback when coach Bill Belichick told him of the trade, which is sending him from one of the NFL's model franchises to the one with the worst record over the last six years.

"I had a lot to think about with my wife, my family, my friends that are close to me, just a lot to think about as far as how do we make this work," Seymour said. "How do we make it happen? I talked with coach (Tom) Cable, and I talked with Mr. Davis as soon as this happened, and I assured them I wanted to be an Oakland Raider. They saw something special inside of me, and I just hope that I can bring what they saw."

Owner Al Davis and Seymour both brushed off reports the Raiders had sent Seymour a five-day letter requiring him to report or face possible suspension.

Cable had remained optimistic through the entire ordeal and believes Seymour can help the Raiders' run defense that ranked last against the run in 2008.

"We've got a lot of good players on that side of the ball, but we needed a piece that would cement the entire group," Cable said. "As this thing went, this was a shock to him. So we chose to really kind of take the path of let this thing work itself out if it's going to. And it did."

After five days of uncertainty, the Raiders are pleased to add a five-time Pro Bowler in time to play in tomorrow's season opener against San Diego.

"It is a morale boost," Pro Bowl cornerback Nnamdi Asomugha said. "I think guys are pretty excited to have him because guys know what he's done in the past. He's got a good reputation so the morale of the team is pretty good right now."