With the NFL regular season past the mid-point and the college football regular season nearing an end, some NFL mock draft speculation has begun. Fox Sports' Peter Schrager has compiled his first mock and projects the Denver Broncos will strengthen their defensive line:

15. Denver Broncos: Devon Still, DT, Penn State: The Broncos struck gold with Von Miller in the first round last year. Look for John Fox to scoop up some interior defensive-line talent in 2012. A 6-4, 310 pound run-stuffer out of Wilmington, Delaware, Still is a four-year starter in Happy Valley. The Denver defense has played extremely well of late. Adding a big presence like Still would only make the young Denver D more dangerous.

The Broncos currently rank 18th in the NFL in total defense and 16th in rushing defense. Still has 16-1/2 tackles for loss at Penn State this season.

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