The expansion Philadelphia Union have acquired the rights to U.S. national-team defeder Danny Califf.

The 29-year-old Califf will return to Major League Soccer after a successful spell in the Danish Supeliga with Aalborg BK and most recently as a member of FC Midtjylland.

Califf has been capped 23 times for the U.S. national team and adds even more depth to head coach Peter Nowak's defense.

"There will be competition for every spot on the pitch" Nowak said in a press release. "But with a seasoned veteran like Danny Califf, we're adding a player who will help us set the bar ever higher. Danny understands the level of commitment our technical staff will demand daily and we're counting on him to not only help anchor our defense but push our younger players to greater heights, too."

Califf won an MLS Cup with Los Angeles in 2002 and spent five seasons in MLS before moving to Europe and has been a regular part of Bob Bradley's set-up during qualifying for the 2010 World Cup. --Goal.com

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