Jeff Agoos’ impending knee surgery will keep the D.C. United defender from playing for the club and for the United States for 2-6 weeks. Agoos, who will undergo arthroscopic surgery to remove a bone chip from his right knee, experienced swelling in the knee prior to D.C.’s match against Tampa Bay on July 4. He played all 90 minutes of the 3-0 loss. An MRI on July 5 night revealed the vexing bone chip and area of bruising to the bone surface. United team doctor William Hazel will perform the procedure on July 7 at his Herndon office. “It is a potential a time bomb waiting to go off,” said United athletic trainer Rick Guter. “It’s better to do it now than to wait before it becomes a bigger problem.” Agoos, named to the United States national team roster for World Cup qualifying matches on July 16 and July 23, will be unavailable to U.S. coach Bruce Arena. Agoos is the second-most capped player on the U.S. roster with 101 international appearances for the USA. “It was certainly unexpected,” Agoos said. “But we all feel that for the benefit of D.C. United, the U.S. national team and potentially the Olympic team, it is something that I needed to take care of now. I’m certainly disappointed not to be a part of the U.S. squad for the first two World Cup qualifiers, but I should be fine for the rest of the qualifiers. In the long run it’s for the best.” “It’s truly unlucky for Agoos,” United coach Thomas Rongen said. “He’s a veteran leader both for United and for the United States, and his presence will be missed on the pitch. Hopefully it won’t be anything too serious and he’ll be back in action by the end of the month.”