The Vikings signed John Carlson this offseason to pair with second-year tight end Kyle Rudolph, drawing comparisons to New England's excellent combination of Rob Gronkowski and Aaron Hernandez. In 62 NFL games, the Minnesota tight end tandem has 163 receptions, 1,768 yards and 16 touchdowns. "To compare us to those two tight ends is not something I'm going to do right now," Carlson said. "We've got a lot of work to do; we have a long ways to go. It's been done. It's being done out there. We have to work to improve to get toward that point."

Julian Edelman hasn't been seen working out with the defense yet, but he has worked out at wide receiver, kickoff returner and punt returner with the Patriots. Edelman wouldn't answer questions about his role. "I don't know if that's team policy," Edelman said.

Rob Gronkowski had a busy offseason, but the Patriots tight end insists he's ready to focus solely on football. "It's training camp time," Gronkowski said. "When it's football time, it's all football, nothing but football, always excited about football. I'm glad to be back. I missed the locker room, missed the teammates, missed competing versus the defense. So far the last two days, having a lot of fun out there competing as hard as we can. "Just here to play some football, baby."

The Patriots released Joseph Addai the day before training camp after he "quit" during his conditioning test, according to a league source. The 29-year old running back played just 20 games over the last two seasons because of injury.

Unable to reach a long-term contract with the Patriots this offseason, Wes Welker was back on the practice field on Thursday. Welker said it was great to be back and that there was no disappointment from not landing the long-term deal he desired. "Everyone tried," Welker said after the practice. "I tried, they tried, and it just didn't work out. It's in the past, and we've moved on to this season, which we expect to be a good one."

The Patriots released Joseph Addai on Wednesday, one day before the team's first training camp practice. Addai had failed the team physical, a league source told ESPNBoston.com Patriots contributor Field Yates. The move comes as a mild surprise, with Addai signing a one-year deal in May that included a $75,000 signing bonus and $50,000 workout bonus.

Chad Johnson's one-year tenure with the Patriots was a disappointment and the wide receiver blames the team for his lack of production. Johnson says he wasn't productive because the team didn't allow him to be himself. "I'm going back to my normal ways," Johnson told the Miami Herald. "My normal ways, when I was at my best, when I got fined, look at the production those years. Usually things don't go right when you try to change the way you do things. I'm back to normal. "My personality was controlled last year. You didn't hear me at all last year. Zero. Zilch. When my mouth is running, it forces me to perform. It's never been vindictive. I never got anybody in trouble. ... When I can be me, I am loose. Everything just flows for me, whether it's the style of play, the way I learn."

The Patriots and tight end Visanthe Shiancoe have agreed to terms on a one-year contract, according to a league source. The former third-round pick of the Giants visited the Patriots last week before continuing on his free-agent tour to Philadelphia.

Deion Branch and Jabar Gaffney are expected to compete for playing time with the Patriots since they each are best utilized outside the numbers. Both receivers are also longtime friends with one another and favorite targets of Tom Brady. Brandon Lloyd is expected to be the complementary outside receiver that Joey Galloway, Torry Holt and Chad Johnson were unable to become.

The Patriots and first-round pick Dont'a Hightower have reached an agreement on a four-year contract, according to a source. Hightower, a linebacker out of Alabama, was the 25th overall pick in April's draft. He is the last of New England's seven 2012 draft picks to agree to terms on a deal. Rookies are due to report to camp on Thursday.