The team's leading tackler a year ago, Trevathan is expected to miss one more game and then return Oct. 5 against Arizona following the team's bye week.
Trevathan, a sixth-round draft choice out of Kentucky in 2012, is coming off a breakout season in which he led the Broncos with 124 tackles and intercepted three passes. He also led the team with two dozen tackles in the playoffs.
Brandon Marshall has started in his absence and leads the Broncos (2-0) with 17 tackles.
Defensive tackle Marvin Austin also practiced Thursday after returning from North Carolina, where his father was seriously injured in a rollover accident.
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