Though the Patriots offense is still mired in a bout of uncertainty, its most integral asset has maintained a confident attitude.

Quarterback Tom Brady has thrown to a redesigned group of receivers during the first seven weeks of the Pats’ offseason workout program, including the last two weeks against the defense in organized team activities. For various reasons, the Patriots’ seven leading receivers from 2012 haven’t been able to join Brady. Wes Welker, Brandon Lloyd, Danny Woodhead and Deion Branch aren’t with the team. Rob Gronkowski, Aaron Hernandez and Julian Edelman are recovering from injuries.

In their place, Brady has worked to develop a new rapport with wide receivers Danny Amendola, Donald Jones, Michael Jenkins, Lavelle Hawkins and Aaron Dobson, along with tight end Jake Ballard. Fourth-round pick Josh Boyce, a wide receiver, is also recovering from a broken toe.

“We’re trying to get all of those guys up to speed,” Brady said last night at his annual Best Buddies Football Challenge at Harvard Stadium. “When you haven’t really played with anybody for a significant time or under a lot of pressurized situations, there’s definitely a learning curve, and we’re going to try to work through that learning curve as much as we can. The practices have been competitive, and we’ve got to be able to keep stringing them together. We’ve got another couple more weeks of spring practice, and that will lead into training camp.”

The most significant concern is still the availability of Gronkowski, who will undergo back surgery this month and might not be ready for the start of the regular season.

“I haven’t inquired too much of what’s going on (with Gronkowski),” Brady said. “That’s all the medical stuff that always sorts itself out. We’ve been working hard with the guys that have been out there, and it’s been fun to be back out on the field.”

Amendola has been Brady’s most high-profile addition, and Welker’s replacement has gotten off to a nice start. It’s been clear through OTAs that the two already have a deeper chemistry than the other new pass catchers.

“He comes in, and he works really hard,” Brady said. “He wants to do everything right. He’s very competitive, so it’s been a lot of fun.”

But of course, Brady is still trying to manage the offense without the NFL’s most productive receiver over the past six seasons. The quarterback said he has remained close with Welker, who has joined a powerful Broncos team.

“I always miss his friendship,” Brady said. “He’s one of my best friends, but we stay in touch. We’ll never lose that. He’s on a great team. He’s moved on, and that’s part of the NFL and something I’ve been accustomed to over the years, is losing some friends.”

New cause

Brady dedicated last night’s game to everyone affected by the Boston Marathon bombings, in addition to his relationship with Best Buddies.

“It’s a great weekend,” Brady said. “We’ve got great support this year. We’ve really had great support since we’ve started the game. This is our fourth or fifth year. It’s the highlight of my year, and to see the Buddies and their excitement over the game, and there’s a little bit of competitiveness.”

Roster adjustments

The Patriots made a couple of tweaks to the roster yesterday.

They waived injured undrafted rookie receiver T.J. Moe and released offensive lineman Tyronne Green. Moe tore his Achilles this week. If he clears waivers, the Patriots could place him on injured reserve. The Pats liked the slot receiver enough to offer him an $8,000 signing bonus and $22,000 in guaranteed base salary, which amounted to the most guaranteed money among any of their current class of undrafted free agents.

Green, who started 13 games last season for the San Diego Chargers, didn’t receive any guaranteed money when he signed a couple weeks ago, which was surprising given his starting experience. He also had a $10,000 weight bonus built into the deal, so the Patriots were clearly concerned about the interior lineman’s conditioning.

Booted up

Edelman was still wearing a walking boot on his right foot last night, so it’s possible he might be out through the remainder of OTAs and minicamp, which is June 11-13. Edelman had surgery on his foot earlier in the offseason program.

Jerod Mayo, Vince Wilfork, Ryan Mallett, Zoltan Mesko, Justin Francis, Ryan Wendell and Amendola were among Brady’s current teammates who also attended last night’s event.