ST. CHARLES, Mo. -- Suspended New York Jets defensive lineman Sheldon Richardson, a former Mizzou star, will be back in court in Missouri on Oct. 5 after pleading not guilty Monday to resisting arrest and traffic charges stemming from his arrest in July.

Richardson's attorney entered the plea in St. Charles County, near St. Louis. Richardson was not present. A spokeswoman for the St. Charles County prosecutor's office said it was not certain if a trial date will be set at the October hearing.

All five charges are misdemeanors. Richardson's attorney declined comment.

Richardson, a former University of Missouri star who lives in the St. Charles County town of O'Fallon in the offseason, was arrested following a chase July 14 that began on Interstate 64. Police say Richardson was driving his 2014 Bentley Silver Spur at speeds up to 143 mph, with a 12-year-old boy, a relative, and two other men inside the car. Police said Richardson appeared to be racing with another car.

Police said they found a loaded semi-automatic handgun under a floor mat on the driver's side, and a probable cause statement said they detected a "very strong odor of burned marijuana."

Prosecutors filed no gun charges because they said Richardson possesses it legally. They declined to file drug possession or child endangerment charges because they said there was not enough evidence.

A conviction for resisting arrest is punishable by up to one year in jail. He could also face a fine of up to $1,000.

The arrest cast doubt on Richardson's future. Two weeks before his arrest, he was suspended by the NFL for four games for marijuana use.

Richardson was the 13th overall pick in 2013, and was named Defensive Rookie of the Year that season. He played in the Pro Bowl last season.

He apologized to the organization and his teammates after news of his arrest came out, something he withheld from even his parents until reports surfaced early in training camp.

During his suspension, Richardson is able to work out at the team's facility, but not practice.