Record-holding American middle-distance runner Shelby Houlihan will not compete at the U.S. Olympic trials despite a statement Thursday from USA Track and Field that raised the possibility.

Days after she blamed a four-year ban for a failed drug test on a tainted burrito and a flawed system, Houlihan remained on the start list for the U.S. Olympic trials, prompting track and field’s anti-doping arm to inform USA Track and Field that Houlihan would not be allowed to run.

The Athletics Integrity Unit wrote to USATF and told the governing body Houlihan would be “strictly prohibited” from running, an AIU spokesperson told The Washington Post in an email.

The letter came after USATF cryptically indicated Houlihan might be permitted to compete. The decision to allow a banned athlete at the trials drew confusion and anger from many USATF athletes and prompted one athlete-led advocacy group to call it “a very troubling precedent.”

By Thursday evening, the U.S. Olympic and Paralympic Committee stated publicly that Houlihan would not compete.

“The U.S. Olympic & Paralympic Committee, together with USATF, can confirm that we will adhere to the [World Anti-Doping Association] Code and any [Court of Arbitration for Sports] decisions that govern athlete participation in sanctioned events,” USOPC CEO Sarah Hirshland said in a statement.

On Thursday morning, Houlihan’s name remained on the start list for Friday’s 5,000-meter preliminary race, seemingly suggesting that USATF would let her race.

“Given there is an active appeal process, USATF will allow any athletes to continue competing until the process is completed,” USATF Managing Director of Communications Susan Hazzard said in a statement.

Houlihan appeared to have exhausted her appeals within track and field’s anti-doping system. She asked for an expedited outcome from the Athletics Integrity Unit as the trials neared. The hearing moved to the Court of Arbitration for Sport, which handed down its ruling Thursday. The AIU, the independent drug-testing arm of World Athletics, lists her case as final.

Houlihan had sought an injunction from the Swiss federal court where athletes can appeal CAS decisions, and the court denied her request because CAS has not yet published its reasoning behind its decision, Houlihan said Friday in an Instagram post. Houlihan said she would have competed only if the injunction had been granted, so as not to jeopardize her or USATF’s legal standing.

The injunction was seen as a long shot. Since her appeal in Swiss court will not be decided for months, if not years, it also extinguishes any faint hopes Houlihan had for competing in the Tokyo Games.

“This ruling means that my goal of making another Olympic team is over for now,” Houlihan said. “I can’t begin to find the words to express how disheartening this is. It absolutely breaks my heart to have my dreams and career taken away for something I did not do.”

It’s possible USATF wanted to protect Houlihan’s spot in the event that she ran a time that made the team and then the Swiss court overturned her ban. The AIU informed USATF that would not be possible.

“The AIU clarified that as a Member Federation of World Athletics, USATF must, in the running of its events, respect and implement decisions of hearing bodies such as the Court of Arbitration for Sport, which are made under the World Athletics Anti-Doping Rules,” an AIU spokesman said in an email to The Post.

“In this case, a final and binding CAS decision confirmed that Ms. Houlihan committed Anti-Doping Rule Violations and was subject to a period of Ineligibility of four years. … Ms. Houlihan’s status during the period of ineligibility means that participation in any competition or activity authorized or organized by a World Athletics Member Federation, such as USATF (i.e., the US Olympic Team Trials) is strictly prohibited.”

Houlihan’s representatives did not return messages.

USATF’s initial statement created frustration even among its own athletes. The advocacy group Clean Sport Collective sent an open letter to USAFT signed by 31 athletes, many of them current or former Olympians, blasting the governing body. They wrote that USAFT signaling it would allow Houlihan to run left them “saddened and angered” and concerned about precedent.

“Many of us have and will proudly represent Team USA, but now you have made us doubt your commitment to us,” the letter read. “How are we as athletes supposed to feel empowered by you, our governing body? How can we trust that you dedicated to fighting for clean sport and clean athletes?”

Tianna Bartoletta, a three-time gold medalist vying for her third Olympic team, signed the letter and individually expressed opposition to the possibility of Houlihan running.

“I just finished my pre meet workout and I’m going to start focusing on myself ahead of tomorrow’s race but before I do listen,” Bartoletta wrote on Twitter. “No, I believe one should not be allowed to line up and race if they have tested positive, been handed a ban, & lost the appeal.”

On Monday, Houlihan announced she had been handed a four-year ban for testing positive for the anabolic steroid nandrolone. She vigorously proclaimed her innocence, laying out the case that trace amounts of nandrolone had come from a pork burrito she had gotten from a food truck. Her coach, Jerry Schumacher, called her ban “a great tragedy in the history of American distance running.”

Houlihan, 28, is the American record holder in both the 1,500 and 5,000. She made the 5,000-meter final at the 2016 Rio de Janeiro Olympics.