A former Metro assistant superintendent was sentenced Tuesday to prison and probation for defrauding the transit agency of more than $180,000 in a scheme involving an agency credit card and janitorial supplies that were never delivered.

Kirby F. Smith, 54, was in charge of Metro’s maintenance and custodial services division when, prosecutors say, he worked with a former National Football League player to repeatedly ring up charges on a Metro credit card in exchange for cash in 2014 and 2015.

Smith pleaded guilty Jan. 31 to violating federal law regarding the supplementation of a government official’s salary.

On Tuesday, a federal court judge for the Eastern District of Virginia sentenced Smith to 14 days in prison and two years’ probation and ordered him to pay $174,054 in restitution to Metro.

Authorities say Smith worked at Metro from 1999 until he was fired in 2015, after the scheme was discovered. Court records show that he was three years from retirement and had worked his way up to management from the position of janitor. In 2013, he was promoted from custodial supervisor to assistant superintendent for grounds maintenance and custodial services.

Kevin Wilson, a public defender assigned to represent Smith, did not respond to a request for comment.

While in that role, prosecutors said, Smith established a relationship with former Washington cornerback Brian M. Carpenter, who played in the NFL in the 1980s and had established a company based in Leesburg.

Carpenter’s company, Flinstone Group, sold janitorial products, some with football-related names, such as an enzyme solvent called Blitz. According to Metro’s Office of Inspector General, Carpenter came up with a scheme in which Smith let him charge his work credit card for supplies that were never delivered.

Instead, Carpenter kept a cut of the fake sale while Smith received a cash payout, according to court records.

To keep the fraud from being flagged by Metro’s internal controls, investigators said, Carpenter enlisted at least 10 companies — most of which were not in the janitorial supply business — to process the payments, allowing him to create fake invoices as if Metro had paid for and received the products ordered.

Carpenter would inform Smith after he charged the card, and Smith would falsely certify with Metro that the products charged to his card were received, according to court records.

Carpenter’s attorney, Robert Jenkins of Alexandria, said his client was just taking advantage of a Metro policy that allowed for the purchasing of supplies well in advance of when they might be needed and without immediate delivery. At some point, Carpenter stopped placing orders with his manufacturers, but if Metro had asked for the supplies that were ordered, he maintains that “he would have complied within a reasonable time,” Jenkins said.

“From Mr. Carpenter’s perspective, this did not start out with an intent to defraud anyone,” Jenkins said.

In total, Carpenter charged $180,617 on the Metro card and gave Smith $10,000, according to court records.

Smith told prosecutors that he needed the money to help pay rent because he was struggling financially to care for eight children, court records said.

In July, Carpenter pleaded guilty in federal court to conspiracy to commit wire fraud. He faces a maximum of 25 years in prison and a $250,000 fine when he is sentenced, court records show.

Investigators, including the U.S. Attorney’s Office for the Eastern District of Virginia, the FBI and Metro’s inspector general, charged Carpenter and Smith in January. Smith pleaded guilty immediately in exchange for his cooperation in the investigation, court records show.