Of course, his time in Denver was short-lived. Greenlaw appeared in just eight regular-season games and two postseason contests, finishing with 43 tackles, a sack, an interception, and a forced fumble.
After the Broncos released him ahead of free agency, the 49ers quickly moved to re-sign Greenlaw, landing him on a one-year, $7.5 million contract.
"He's one of the best linebackers I've ever coached," head coach Kyle Shanahan said this week when asked what Greenlaw's return means for the team. "I've been around some good ones. What he's meant to the Niners organization, and we hated being away from him, and we're pumped to get him back."
Greenlaw's return also reunites him with All-Pro linebacker Fred Warner, recreating one of the NFL's top linebacker duos and giving him extra motivation heading into the 2026 season.
"Fred, he came in a year before me, but I swear, it just feel like a certain feeling we got when we just play," Greenlaw said on The Set podcast with Terron Armstead (h/t to Taylor Wirth of NBC Sports Bay Area for the find). "It's not for each other, but when we look across that, and we see each other, you dang right it's for each other. It's like, you're not going to let me down, I'm not going to let you down.
"It's such a weird connection, but he knows I'm going to put all I got on the line, and I know he's going to do the same, and that's all you can ask for. It's like a partner in crime. It's all going to work out like it's supposed to, but I'm thankful for it all. I'm thankful for all the relationships that I've had for those six years, and kept along this past year, and will continue to keep along this year, too, as well."
Greenlaw emphasized that Warner makes him better, which should help him rebound from a disappointing 2025 season in Denver.
"He's the standard, for sure," Greenlaw said.
Even observing Warner in practice—his attention to detail and relentless intensity—pushes Greenlaw to elevate his own game.
Reuniting with Greenlaw has equally fired up Warner. He recently put the NFL on notice, highlighting that the duo's return is bad for opposing offenses.
"Every single time I've played with Dre, for like the seven years that we played together, there's an unspoken language on the field," Warner said earlier this month, "where I don't have to turn to him and be like, 'Hey Dre, look for this.' We're moving together in unison, and it was just so easy because we just had this great vibe with one another.
"It allows you to play even more free. Dre, he's one of the best athletes I've ever played with on a field, and just so ferocious and relentless in the way that he plays the game. You just love playing with guys like that, who just are willing to give it up."
The 49ers will rely on this elite linebacker pairing as they aim to stay competitive in a strong NFC West that also boasts the Seattle Seahawks and Los Angeles Rams.
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