Huff will return to coach the offensive line, a position he coached at Boise State from 2007-09. Avalos' position group will be announced at a later date, as Harsin continues to assemble his staff.
Each is a graduate of Boise State.
"I'm very excited to be able to retain two Broncos in Scott Huff and Andy Avalos," Harsin said. "Both are quality coaches and people, and excellent recruiters. I think it's important we continue the tradition of the program, and each has played a key role in the past for Boise State - both as a coach and a player. I'm also excited to get Coach Huff back with the position he played for Boise State.
"Both Coach Huff and Coach Avalos had excellent playing careers, and they bring great passion and energy to the program."
Huff both played and coached with Harsin at Boise State, and Avalos was a student-athlete with the Broncos while Harsin was an assistant coach.
Huff has spent the last eight seasons at Boise State, and while working with the offensive line, the Broncos averaged less than a sack allowed per game. Boise State led the nation in the statistical category in 2009 (0.36 per game), giving up just five sacks the entire season. The Broncos also ranked tied for fourth-nationally in 2008 (1.00) and 20th-nationally in 2007 (1.3).
The offensive line helped contribute to one of the most successful runs in school history under Huff, including two perfect regular seasons, and a 14-0 season in 2009 that culminated with a victory in the Tostitos Fiesta Bowl.
"I first want to thank Coach Harsin for this opportunity to stay in Boise and continue to build on what we have worked so hard on the past several years," Huff said. "I'm excited about coaching alongside Bryan, and looking forward to returning to coach the offensive line."
Ryan Clady, Andrew Woodruff and Nate Potter were each named first-team All-Western Athletic Conference under Huff.
Huff coached tight ends in 2006, part of the Broncos' first Tostitos Fiesta Bowl victory, and from 2010-13. He was also the Broncos' special teams coordinator each of the last two seasons.
The Broncos have won five conference championships and five bowl games with Huff as an assistant, and three each while Huff was a student-athlete.
A native of Phoenix, Ariz., Huff started 40 games at center during his four-year career (1999-2002), earning first-team All-WAC honors as a senior. In his final collegiate campaign, Huff anchored an offensive line that led the nation in both scoring and total yards.
A 2002 graduate of Boise State (business administration), Huff earned his master's degree in secondary education-curriculum from Arizona State.
Avalos returned to Boise State in 2012, and has coached the defensive line the last two seasons. Three players have combined to earn five All-Mountain West honors since his arrival, including two-time first-team honoree Demarcus Lawrence, and fellow first-team recipients Mike Atkinson and Ricky Tjong-A-Tjoe. Lawrence also earned All-America accolades this season from both the Walter Camp Foundation (second team) and SI.com (honorable mention).
"I'm very thankful for the opportunity to stay with this program and continue its growth with Coach Harsin and the staff he is bringing in," Avalos said. "We have an outstanding group of student-athletes returning, and the future is very bright. Bryan is a great Bronco and coach, and the leadership of this program is in great hands."
The Broncos ranked 11th-nationally in sacks last season (2.92), and this season the Broncos rank 23rd in tackles-for-loss (7.0). Lawrence has ranked amongst the national leaders in sacks in each season under Avalos, finishing 2012 ranked tied for 18th (0.86 per game). He ranks eighth-nationally this season (1.0).
Avalos joined the Broncos from Sacramento State, where he coached linebackers in 2011. He was the defensive line coach at Nebraska-Kearney from 2009-10, and was a defensive graduate assistant at Colorado for three seasons, where he worked with outside linebackers.
Avalos was a four-year letterwinner at outside linebacker for the Broncos from 2001-04, earning first-team All-WAC honors in each of his final two seasons. Avalos left Boise State ranked fourth all-time with 365 tackles, and led the Broncos in the statistical category in each of his final three seasons.
The Broncos won three conference championships and two bowl games during his collegiate career.
Originally from Corona, Calif., Avalos earned his criminal justice degree at Boise State in 2004, and his master's in education at Colorado in 2008.