Califf is one of many sturdy options in the centre-back position for USA coach Bob Bradley. Beginning his club career with MLS side LA Galaxy in 2000 after two years of successful University football, Califf - a no nonsense character - spent the next three seasons in sunny southern California forging a reputation as one of the top American backs, winning a league title in 2002 and a US Open Cup during his time with the club.
After a season in nearby San Jose in 2005, Califf moved over to northern Europe to try his luck overseas. In his first year at Danish powers Aalborg, Califf became an important cog in the side's rearguard, playing nearly every game. He was named captain the following season and helped the side to a national title. In 2008, Califf, with a distinctive full sleeve tattoo on his left arm, moved on to Danish top-flight rivals Midtjylland before returning to MLS in 2010 to lead league new boys Philadelphia Union in their inaugural season.
Earning his first cap in 2002, the year he helped LA to the MLS league crown with some dominating performances, Califf has become an able deputy to Carlos Bocanegra and Oguchi Onyewu as one of the two centre-backs in Bob Bradley's American line-up. He has played for the US in two successful CONCACAF Gold Cup campaigns and at the 2003 and 2009 FIFA Confederations Cups.