New San Francisco 49ers cornerback Richard Sherman says playing in the NFC West and having the opportunity to face his former team, the Seattle Seahawks, twice per season played a role in his free-agent decision, telling The MMQB on Sunday that "I'm vengeful in that way."

Sherman acknowledged his feelings after seeing the reaction from Seahawks fans to his signing with one of their rivals.

"I love the fan base to death, and I loved playing there. It was such a great opportunity. I helped the organization get to a great place and stay there," Sherman told The MMQB. "But now it's like I abandoned them. People are out there burning my jersey. Come on. I'm not the one who let me go. They let me go. I didn't abandon anybody."

The 49ers and Sherman agreed to a three-year contract that was officially announced by the team Sunday. Terms of the contract were not disclosed, but Sherman told ESPN's Josina Anderson on Saturday that the incentive-laden deal is worth up to $39.15 million.

Sherman told The MMQB that the contract contains guarantees that roll over to the following year if he makes the Pro Bowl.

"I don't think any agent in the business could have done a better job of negotiating this contract," Sherman said. "As long as I'm content with what I'm making, nothing else matters to me.

"Once I make a Pro Bowl, $8 million the next year is guaranteed for me. It gives me the ability to control my destiny. The 49ers have skin in the game. I have skin in the game. In my former contract, no matter what I did this year, nothing would be guaranteed to me next year. I couldn't feel secure in my contract. Now, if I play the way I know I'm capable of playing, I know I'm going to get paid."

Sherman said he called the Seahawks to gauge their interest on matching the 49ers' offer but was turned down based on the incentives. He also reached out to the Oakland Raiders and Detroit Lions before finalizing the deal in San Francisco.

The MMQB also detailed some of the negotiations between Sherman and the 49ers, including general manager John Lynch and executive vice president of football operations Paraag Marathe. Sherman was acting as his own agent, and Marathe said he was impressed by the cornerback's preparation.

"Richard came into the meeting with us having read all the contracts for all the top cornerbacks past and present," Marathe said, adding that Sherman "studied our contracts and knew who'd we'd given real guaranteed money to."

San Francisco hopes Sherman can make a big impact even as he turns 30 later this month and is coming off an Achilles tendon injury that cost him half of the 2017 season. Sherman also had a cleanup surgery on his opposite ankle during the offseason.

The Associated Press contributed to this report.