SANTA CLARA, Calif. -- The San Francisco 49ers' trade for quarterback Jimmy Garoppolo shook up the NFL world on Monday night, if only because of when it happened and because it had seemed the New England Patriots had little interest in parting with him.

On Tuesday morning, 49ers general manager John Lynch spoke on the team website and revealed some of the details of how the Garoppolo trade came to fruition. According to Lynch, the Niners and Patriots began talking a trade in the offseason but could not come to an agreement. Of course, we know a big reason for that was the Patriots' reluctance to trade Garoppolo.

Here's what New England coach Bill Belichick said to New England reporters and ESPN's Mike Reiss on Tuesday morning about how they finally arrived at a point where they were willing to trade Garoppolo:

"It's definitely not something we wanted to walk away from," Belichick said. "I felt like we rode it out as long as we could. Over a period of time, we explored every option possible to try to sustain it. But at this point, felt like we had to make a decision.

"It's a very complex situation on multiple levels. This is really the last window that we had [the trade deadline is Tuesday at 4 p.m. ET], and we did what we felt was best for the team."

In other words, the Patriots preferred to keep Garoppolo, but since he'll become an unrestricted free agent and New England apparently is unwilling to tag him or sign him to a lucrative contract extension to continue as their backup in the offseason, it was necessary to move him now to get the most value.

So the Niners sent their original second-round pick to the Patriots, a pick that figures to be quite early in that round given the 49ers' record.

Which now begs the question of what, exactly, the 49ers are going to be getting in Garoppolo? The sample size is small, as Garoppolo has fewer pass attempts than rookie C.J. Beathard, but if anyone knows what Garoppolo is, it's those who coached him, played with him and covered him the past three-plus seasons.

With that in mind, here's a look at what they say about Garoppolo:

Belichick: "I have a tremendous amount of respect for Jimmy. I couldn't ask for him to give us any more than he has given us. The 49ers are getting a good player, they are getting a good person, and they're getting a great teammate, and they are getting a good quarterback. And Jimmy is getting a good coach. His career is moving forward. He's a talented individual. He was a great person to coach. I met with him weekly. But as his career moves forward, we have to look at our team, both this year and beyond."

QB Tom Brady via his weekly Westwood One radio interview: "He was a great teammate and a great friend. He always will be. I want nothing but the very best for him. He's earned the trust of his teammates and the respect of his teammates, and that's all you can ask for as a player."

"He's put in all the effort. I've watched him for three-and-a-half years and really enjoyed working with him. Hopefully he goes on and does a great job."

I also e-mailed Reiss for some of his thoughts on Garoppolo. The first thing he mentioned was Garoppolo's passion for leadership and his efforts to connect with every player in the Patriots' locker room. It's something Reiss noted is a hallmark of Brady, and Garoppolo did it with his younger teammates as a rookie in 2014 and continued to do so during his career in New England.

As for his on-field ability, Reiss first points to Garoppolo's quick release forged by a "smooth, compact delivery." Garoppolo also impressed Patriots observers with his ability to process information quickly and make good decisions.

Beyond Garoppolo's small sample size, some of the potential weaknesses include height that isn't prototypical -- he's 6-foot-2 -- and what seems like a lack of good decision-making when it comes to his own health. He injured his right shoulder in Week 2 of last season when he decided not to throw the ball away, took off running and then took on linebacker Kiko Alonso. The injury cost him the rest of that game and the next two and forced the Patriots to go with third-stringer Jacoby Brissett.

Clearly, Garoppolo still has a lot of proving to do when it comes to producing on a consistent basis in the league. To this point, there have been some flashes of that ability, and by all accounts, he has the intangibles that Lynch and coach Kyle Shanahan covet.

It will be up to the Niners to help Garoppolo put it all together and cement himself as their franchise quarterback for the long haul.