Kugler, who will coach guards and centers, is a 28-year coaching veteran who has 18 seasons of experience coaching the offensive line. His previous stops include Detroit (2001-05), Buffalo (2007-09) and Pittsburgh (2010-12).
Modkins, the Broncos running backs coach, is a 23-year coaching veteran who has spent the past 10 years in the NFL as an offensive coordinator or running backs coach. He has worked with three 1,000-yard rushers during that span: C.J. Spiller (1,244 yards) with Buffalo in 2012, Reggie Bush (1,006 yards) with Detroit in 2013 and Jordan Howard (1,122 yards) with Chicago this past season.
Quarterbacks coach Mike Sullivan has coached for 23 years, including 15 seasons in the NFL with Jacksonville (2002-03), New York Giants (2004-11, 2015-17) and Tampa Bay (2012-13).
He served as offensive coordinator for the Giants the last two seasons.