(ENGLEWOOD, Colo.) -- As Denver Broncos head coach John Fox recovers from heart surgery, defensive coordinator Jack Del Rio will take over as the team's interim head coach.
Fox will undergo aortic valve replacement surgery early this week at a Charlotte N.C. hospital. On Saturday, Fox became dizzy playing golf and tests determined he needed surgery immediately.
"I look forward to returning to coaching as soon as possible," Fox said in a statement.
Del Rio is in his first season as the Broncos defensive coordinator. He took over for previous coordinator Dennis Allen, who was hired as the Oakland Raiders head coach during the offseason.
Del Rio's ascension isn't much of a surprise. Before he was with Denver, Del Rio was the Jacksonville Jaguars head coach from 2003-2011, winning 68 games during that span.
Luckily for Del Rio and the Broncos, the team is 7-1 and the transition from Fox to Del Rio was made easier as the event happened during the team's bye week.
Fox is expected to return to the team at some point this season.
Copyright 2013 ABC News Radio