Atlanta Falcons' star quarterback Michael Vick has pleaded not guilty to charges of organising dog fights.
Vick appeared in court in Richmond, Virginia on Thursday
Vick, 27, and three other men entered their pleas on Thursday, and Vick was released without bond until a trial on 26 November.
Vick was booed by a crowd of hundreds outside the US District Court in Richmond, Virginia.
He had already been ordered to stay away from pre-season training, which began on Thursday.
"I take these charges very seriously and look forward to clearing my good name," Vick said in a statement read outside court by Billy Martin, his lawyer.
"I respectfully ask all of you to hold your judgment until all of the facts are shown.
"Above all, I would like to say to my mom I'm sorry for what she has had to go through in this most trying of times. It has caused pain to my family and I apologize to my family."
NFL commissioner Roger Goodell earlier said he would review whether Vick had violated league policies.
The Falcons will withhold disciplinary action until after the league review.
Atlanta play their first pre-season match against the New York Jets on 10 August, with the regular season beginning in Minnesota on 9 September.
Vick, the first overall pick in the 2001 college draft, last season became the first quarterback ever to rush for more than 1,000 yards.
Since the charges were brought, pressure has been mounting on the league and the Falcons, particularly from animal-rights groups.
There were demonstrations at Falcons' headquarters in Georgia on Monday, following similar scenes outside NFL offices in New York last week.
Activists also put pressure on companies that have endorsements deals with Vick to cut their ties and Nike has already delayed the launch of a new shoe bearing his name.