FOXBORO, Mass. -- The New England Patriots signed Pro Bowl safety Rodney Harrison, their second significant move to bolster their defense in less than 24 hours.

Patriots spokesman Anthony Moretti said Harrison agreed to terms with New England on Tuesday night. The contract is six years, $15 million. The Patriots also signed linebacker Rosevelt Colvin on Tuesday.

Harrison, 30, was plagued by a groin injury last season -- his ninth with the Chargers. He started 13 games, recording two interceptions, two sacks and 88 tackles, including 12 in the final game of the year against Seattle, tying a season high.

"I thought that I'd be playing in the Canadian League before I'd be playing here," Harrison told the San Diego Union-Tribune. "But Coach (Bill) Belichick stepped up. He showed interest and, whatever he said and committed to do (by phone), he did. He said, 'We want you here.' "

Harrison's signing gives the Patriots some flexibility in their secondary. Starting safety Tebucky Jones, whom the team has labeled its franchise player, is unsigned, as is safety Victor Green.

Harrison was named to the Pro Bowl in 1998 and 2001. One of the NFL's most physical hitters in the secondary, Harrison's best year statistically was in 2000, when he had six interceptions, six sacks and 127 tackles.

The acquisition of Harrison might lend some credence to rumors the Patriots would consider trading Jones. There have been reports, and league sources have confirmed for ESPN.com, that the New Orleans Saints are interested in acquiring Jones.

Saints coach Jim Haslett is said to covet Jones, 28, whose marvelous physical skills are sometimes countermanded by inconsistent play. New Orleans has two first-round draft choices and might be willing to part with one to improve a secondary that is the team's weakest position. New England also has two first-round picks and could use Jones to bolster its cache.

The Saints almost certainly would want to formulate a long-term agreement with Jones before any trade. Agent Gary Wichard said Tuesday night he has not talked to New Orleans officials.

On the other hand, the Patriots simply might have added Harrison to improve their own secondary with a quality third safety in the likelihood they lose backup Victor Green in free agency. The Patriots often play three safeties in their "Big Nickel" package.

The team was to have spoken with the representative for another free agent strong safety, former Pittsburgh Steelers starter Lee Flowers, on Wednesday. It is unlikely now the Patriots will pursue Flowers.

Harrison, 30, was released by San Diego for salary cap reasons but also because he no longer fit well into coordinator Dale Lindsey's scheme. A former Western Illinois star, selected by San Diego in the fifth round of the 1994 draft, Harrison one of a disappearing breed.

Known more for run support than pass coverage, Harrison still has 26 career interceptions. But the trend in the league is toward the more mobile safety, a player with range who can cover wide receivers in the slot and play the pass out of "base" alignments. No matter the trend, Belichick will likely find a way to use Harrison to his advantage.

It appeared on Monday that Harrison, who many believed wanted to stay in the AFC West, would sign with the Oakland Raiders. He visited with them and then returned to his offseason home in Atlanta to discuss his career options with his fiancé. While there, Denver Broncos coach Mike Shanahan attempted to arrange a visit with him, but the Patriots beat him to the punch.

Harrison took a Monday red-eye to Boston and, less than 24 hours later, he represented the Patriots' second big catch of an eventful Tuesday. The addition of Colvin earlier in the day, with a seven-year contract worth about $30 million, will give New England its best pass rusher in years.

Saying he was "shocked and excited," Harrison lauded Belichick and said he actually wanted to escape the AFC West.

"I kind of wanted to start over and get disconnected from that," he said.

The Patriots also signed special teams ace Chris Akins, an unrestricted free agent who played last year for the Cleveland Browns. He has 57 special teams tackles during his four-year career, including a career-high 25 last season.

Akins also has played for Dallas and Cleveland. Terms of the deal were not disclosed.

Information from The Associated Press and ESPN.com senior writer Len Pasquarelli was used in this report.