Graham's athletes have been under suspicion

Track coach Trevor Graham is expected to be charged in San Francisco as soon as Thursday with obstructing a federal steroids investigation, two Justice Department officials with knowledge of the investigation told The Associated Press.

Graham has worked with several athletes who were suspended or investigated in doping cases:

Justin Gatlin
Gatlin tied Asafa Powell's world record of 9.77 seconds in the 100 meters in May. He won the 100 at the 2004 Olympics and 100 and 200 at the 2005 world championships. He also finished third in the 200 and won silver with the 4x100 relay team at Athens. Gatlin tested positive for testosterone after a relay race in Kansas in April. In August, he acknowledged testing positive for doping, and the U.S. Anti-Doping Agency handed down a ban of no more than eight years, which Gatlin has said he will appeal. In college, he also tested positive for a banned substance contained in medication for attention deficit disorder. His original two-year ban was reduced by the IAAF.

Marion Jones
Jones won five medals, including three gold, at the 2000 Olympics. Ex-husband and banned shot-putter C.J. Hunter and BALCO founder Victor Conte both have alleged she used performance-enhancing substances. She never has tested positive and firmly denied all accusations, but has been under scrutiny in BALCO probe. Former boyfriend Tim Montgomery, father of her child, was banned on evidence in the BALCO scandal without failing a test.

Tim Montgomery
Montgomery ran 9.78 to break the 100 world record in September 2002, shaving 0.01 off Maurice Greene's time. Was charged by the U.S. Anti-Doping Agency in the BALCO scandal despite never failing a test. He received a two-year ban, was stripped of his world record and retired.

Dennis Mitchell
Mitchell won gold with the U.S. 4x100 relay team at the 1992 Olympics and bronze in the 100. He also won a 4x100 relay silver medal at Atlanta in 1996. In 1998, he was banned for two years after testing positive for elevated levels of testosterone.

C.J. Hunter
Hunter, ex-husband of Marion Jones, won gold in the shot put at the 1999 world championships. He failed four tests for the steroid nandrolone in 2000 and missed the Sydney Olympics. He retired and was suspended for two years in 2001.

Jerome Young
Young won gold with the 4x400 U.S. relay team at the 2000 Sydney Olympics. He was stripped of his medal after it was revealed he tested positive for nandrolone in 1999. Young, the world 400 champion in 2003, was banned for life in 2004 after testing positive for EPO.

Alvin Harrison
Harrison won gold as part of U.S. relay teams at the 1996 and 2000 Olympics. Though he never failed a test, he accepted a four-year ban in October 2004 after admitting using EPO, among other performance-enhancing drugs, in the BALCO scandal.

Calvin Harrison
Twin brother of Alvin, he won Olympic gold in the 4x400 U.S. relay at Sydney 2000. He was suspended for two years in August 2004 after his second doping violation. He was found guilty of using the stimulant modafinil at the U.S. championships in June 2003. He also tested positive for the stimulant pseudoephedrine at the 1993 U.S. junior indoors and served a three-month ban.

Michelle Collins
Collins won the 200 titles at the 2003 world indoor and U.S. championships. She testified before the BALCO grand jury, and her eight-year ban was reduced to four. USADA charged her with doping -- including use of the steroid THG and EPO -- based on patterns observed in her blood and urine tests, and she was stripped of her titles.

Patrick Jarrett
The Jamaican sprinter, the only man to beat Maurice Greene in 2001, was banned for two years in 2001 after testing positive for steroid stanozolol at his national trials.