Porter wasn't allowed to fly to San Diego for the Broncos' last game on Oct. 15 but he returned after the bye week and participated in practices Monday and Wednesday on a limited basis.
He missed Thursday's workout and coach John Fox said he was day to day.
Porter said earlier in the week he was eager to face his former team, the New Orleans Saints, who visit Denver on Sunday night.
The last time Peyton Manning and Drew Brees squared off, in the 2010 Super Bowl, it was Porter who stole the spotlight, returning an interception 74 yards to seal the Saints' 24-17 win over the Indianapolis Colts.
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