Tennis • Defending champion Rafael Nadal pulled out of the London Olympics on Thursday with an undisclosed injury, leaving the tennis competition without one of its leading stars and robbing Spain's team of its flag bearer for the opening ceremony.

Nadal won the French Open for a record seventh time this year but has struggled with left knee problems at times during the season. Shortly after winning his 11th Grand Slam title at Roland Garros, he lost to 100th-ranked Lukas Rosol in Wimbledon's second round.

Head of Big Ten may gain power

College conferences • In the wake of the scandal at Penn State, the Big Ten Conference is considering a plan to give its commissioner the power to punish schools with financial sanctions, suspensions and even the ability to fire coaches.

An 18-page plan being circulated among Big Ten leadership raises the possibility of giving Commissioner Jim Delany such authority, the Chronicle of Higher Education reported Thursday. The plan, which the Chronicle posted online, suggests that in certain circumstances requiring "immediate and decisive action," the commissioner would have unilateral authority to "take any and all actions" in the best interest of the Big Ten.

N.Y. court upholds trainer's ban

Horse racing • A midlevel New York court on Thursday upheld Kentucky Derby-winning thoroughbred trainer Rick Dutrow Jr.'s 10-year ban from the sport for drug violations, though he can keep working while his attorney pursues an additional appeal.

The Appellate Division unanimously rejected Dutrow's argument that his hearing was unfair and that a top New York racing official should have recused himself from the disciplinary case.

From wire reports