The dependable Holmes started for his third season on the offensive line (his second year as the starting center) as a senior in 2012. He appeared in and started 12 games (all but Stanford, which he missed after spraining his ankle against Syracuse). He was among 6 finalists for the 2012 Rimington Trophy and made 2012 SI.com All-American honorable mention and All-Pac-12 first team. He also made the ESPN.com, CBSSports.com, Phil Steele and CollegeFootballNews.com All-Pac-12 first teams. He was named the USC's Offensive Lineman of the Year and also won the Trojan Way Leadership Award and the Trojan Football Alumni Club Award (top GPA). He was a Senior Bowl invitee.
Holmes started for his second season on the offensive lineman as a junior in 2011, performing exceptionally well at center in 2011 after playing offensive guard in 2010. He made the 2011 All-Pac-12 second team and the Phil Steele All-Pac-12 second team. He was moved from guard to center in 2011 spring practice. He missed 2011 spring practice because of a shoulder injury.
Holmes started all of 2010 at right offensive guard as a sophomore and did a commendable job. He made 2010 All-Pac-10 honorable mention.
Holmes was a backup offensive guard as a redshirt freshman in 2009. He appeared briefly in 3 games in 2009 (San Jose State, Washington State, Arizona State).
Holmes redshirted as a freshman offensive guard in 2008, his first year at USC.
His 2007 honors included Prep Star All-American, EA Sports All-American third team, ESPN 150, Super Prep All-Farwest, Prep Star All-West, Long Beach Press-Telegram Best in the West Best of the Rest, Tacoma News Tribune Western 100, Cal-Hi Sports All-State first team, All-CIF Pac-5 Division first team, Los Angeles Times All-Star, Orange County Register All-Orange County first team and All-Trinity League Co-Lineman of the Year as a senior offensive lineman at Mater Dei High in Santa Ana (Calif.).
As a junior in 2006, he made Cal-Hi Sports All-State second team, Cal-Hi Sports All-State Underclass first team, Los Angeles Times All-Star and All-Trinity League first team.
He was named to the 2005 Cal-Hi Sports All-State Sophomore first team. Current Trojans Matt Barkley, Victor Blackwell and Max Wittek also prepped at Mater Dei.
He received his bachelor's degree in communication at USC in the spring of 2011 and has begun work on a master's degree in communication management. He has a B average (3.31 GPA). He made the 2011 Pac-12 All-Academic second team. He made 2010 Pac-10 All-Academic honorable mention. He and 15 of his USC teammates spent 5 days in Haiti in the spring of 2012 building homes and assisting those in need. His father, Mike, lettered at defensive end at Michigan in 1974 and 1975. His brother, Alex, was a 4-year (2000-02, 2004) letterman tight end at USC who had 82 career receptions and was a member of USC's 2003 and 2004 national championship squad, and then played with the NFL's Miami Dolphins in 2005. His brother-in-law is former USC (1999-2002) All-American and current NFL All-Pro safety Troy Polamalu.