Washington-- Roger Clemens has been acquitted on all charges by a jury that decided he didn't lie to Congress when he denied using performance-enhancing drugs.

Jurors returned their verdict Monday after close to 10 hours of deliberation. The outcome brings an end to a 10-week trial that capped an expensive, five-year investigation into one of the greatest pitchers in the history of baseball.

The 49-year-old Clemens was accused of perjury, making false statements and obstructing Congress when he testified at a deposition and at a nationally-televised hearing in February 2008. The charges centered on his repeated denials that he used steroids and human growth hormone during his 24-year career.

The verdict is the latest blow to the government's pursuit of athletes accused of drug use.

Last week, Clemens' lawyers tore into the prosecutors' case against the former pitching great during closing arguments, attacking the government for bringing the matter to court in the first place and mounting one last assault against Clemens' chief accuser.

Federal prosecutors painted Clemens as a liar who did not want to tarnish his name. "He chose to lie, he chose to mislead, he chose to provide false statements, to impede Congress' legitimate investigation," prosecutor Gil Guerrero said last week.

Clemens was charged with perjury, making false statements and obstructing Congress. The heart of the charges centered on his repeated denials that he used steroids or human growth hormone. Jurors heard 26 days of testimony over more than eight weeks.

"When you take that oath, you've got to tell the truth," Guerrero said last week in a packed courtroom that included Clemens' wife and four sons.

Guerrero accused Clemens of coming up with a "cover story" about the injections received from his former strength coach, Brian McNamee. Clemens told Congress the injections were for vitamin B12 and the local anesthetic lidocaine, but McNamee testified that he injected the pitcher with steroids and HGH.