Now he's part of Denver's deep linebacker corps that's being tested following injuries to Danny Trevathan (dislocated left kneecap) and top tackler Brandon Marshall (sprained right foot) last weekend.
Marshall is expected back for the playoffs. He's hoping the Broncos can wrap up a first-round bye in Cincinnati on Monday night without him. That would give him a month to get well before Denver would host a divisional round game the weekend of Jan. 10-11.
The Broncos claimed Davis off waivers Nov. 13 from New Orleans, where he played primarily on special teams, although he didn't arrive in time to play at St. Louis three days later.
''I just wanted to bring something to the team. Special teams, backup on defense, whatever it was, I just wanted to do something positive and just bring something to the team every day,'' Davis said.
Davis found an immediate comfort level in Denver. Not just on special teams, but on defense, where he fits the mold that defensive coordinator Jack Del Rio favors in his linebackers: smaller, quicker, instinctive.
''It felt like home. It didn't feel like I was coming here as much as an outsider or anything,'' Davis said. ''It just felt like the right fit. As soon as I got here, it felt good.''
And he proved a quick study.
He quickly began appearing in some of the team's specialty packages ahead of drafted rookies Lamin Barrow and Corey Nelson. When Marshall got hurt Sunday, Davis logged 28 snaps from scrimmage and with Von Miller lined up at defensive end, he was often the only linebacker on the field when Denver sealed its 22-10 win at San Diego.
''I think he's adapted quickly,'' coach John Fox said. ''He does have good football awareness and football character. I think he's done a very good job in this short time.''
Davis could find himself with an even bigger role over the next two weeks as the Broncos await Marshall's return.
It's quite a turn of events for Davis, who went undrafted after earning All-Big Sky Conference honors with 131 tackles his senior year at Sacramento State. His poor times in the 40-yard dash scared away NFL scouts.
''Aw man, yeah. I think it was just me putting too much on myself, trying to go out there and be fast and trying to do too much,'' Davis said. ''I think it was just me putting too much on myself, trying to do too much, trying to be too fast. I mean, I'm out there running sprints the day before, trying to be the best I can be and then by the time I got to pro day my body, I think my body was just gassed.''
The Saints signed him a month before training camp started, and he was waived every month starting in August, bouncing back and forth from the practice squad to their 53-man roster.
He'd been through this drill so many times, he thought nothing of it when he was demoted in November.
''Their plan was to bring me back,'' he said.
So, he turned off his phone when he went to work out on the Saints' off day.
When he turned it back on, his phone began buzzing with all the messages he'd missed.
''It was crazy that my phone was off at such a critical time,'' Davis said. ''Because truthfully, I didn't really think I'd be going anywhere.''
Now he's trying to help Denver go deep in the playoffs.
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