“Going from a 4-3 to a 3-4 was a huge difference, especially not being able to practice in the defense,” Greenlaw said on The Set with Terron Armstead. “It’s like, for me, the fact that I’m not healthy, I don’t feel that twitch or that gear that I felt like I need to have, but, obviously, I’m out here trying to do everything I can to be on the field. It makes it tough when you pay a guy $11 mil and he’s only on the field 50 percent of the time. It made it tough for me. It made it to the point where it kind of makes you not happy.

“Now I’ve got to slowly come in and take reps from somebody else — the linebackers were playing really, really good at the time, so now I’ve gotta come in I’m taking reps from this guy. And now it’s like, OK, we’re splitting reps, how are we going to do it? One week it’s this, one week it’s that, and it’s like, I’ve never been in that position before for one and, for two, yeah, I just wasn’t happy. That’s really what it boiled down to at the end of the day.”

It makes perfect sense for Greenlaw to feel this. The learning curve of a new defense, especially a 3-4 lineup, is like learning a new language.

And the fact that he was missing time due to injury just made it worse. He couldn’t get his reps in to feel comfortable in the defense and be the best version of himself.

Greenlaw was spending more time rehabbing and staying in shape than he was getting acclimated to the Broncos’ defense. It was an unlucky year for him, which led him to be unhappy. Who could blame him?

But that doesn’t make him regret joining the Broncos or appreciate the people he played with. It all worked out in the end for him as he’s back with the 49ers.

“Everything works out for a reason. I don’t regret none of it. I’m thankful for it all, for Sean (Payton) and everybody that accepted me into that organization, teammates and all. But, yeah, I’m excited to be a Niner.”

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