As the N.F.L.’s 15-month investigation into sexual misconduct claims against Deshaun Watson neared a resolution, one of his accusers filed suit Monday against Watson’s former team, the Houston Texans, alleging that the organization “turned a blind eye” to Watson’s behavior toward female massage therapists.

Watson, a quarterback who was traded to the Cleveland Browns in March, reached settlements last week with 20 of the 24 women who accused him of assaulting or harassing them during massage appointments that took place between 2020 and 2021, when he was on the Texans’ roster. The civil suit against the Texans was filed by one of the four women who has not settled with Watson. She said the team enabled his behavior by providing Watson a nondisclosure agreement to give to therapists and by supplying the venue he used for some of his appointments, as The New York Times reported earlier this month.

“We are aware of the lawsuit filed against us today,” the Texans said Monday in a written statement. “Since March 2021, we have fully supported and complied with law enforcement and the various investigations. We will continue to take the necessary steps to address the allegations against our organization.”

Watson has repeatedly denied all the accusations and, through his lawyers, acknowledged having consensual sexual contact with three of the women who sued him. In March, two Texas grand juries declined to indict Watson on criminal charges. In between those cases being dismissed, the Browns traded for Watson and signed him to an unprecedented, fully guaranteed five-year contract worth $230 million.

The lawsuit against the Texans was filed the day before Watson was expected to appear at an N.F.L. disciplinary hearing with the former federal judge Sue L. Robinson, an arbiter jointly appointed by the league and the players’ union. It is the league’s first personal conduct case to be heard by a disciplinary officer instead of Commissioner Roger Goodell, a protocol established in the 2020 collective bargaining agreement.

In briefing materials provided to Robinson and the union before the hearing, the N.F.L. recommended that Watson be suspended indefinitely and have to wait at least a full season to apply for reinstatement, according to two people who have reviewed the league’s materials. They spoke under the condition of anonymity because the N.F.L. has not publicly commented on the findings of its investigation.

The Wall Street Journal first reported the N.F.L.’s recommendation.

The hearing was scheduled because the league and Watson’s representatives were not able to negotiate a mutually agreed upon penalty, indicating that there is a wide gulf between what each side would accept. An indefinite suspension would give the league the flexibility to adjust its discipline if any new allegations were made against Watson or if new information pertinent to the investigation came to light through avenues such as the ongoing civil cases or the new legal action filed against the Texans.

The union was expected to argue against significant punishment, in what will be the first test for the new disciplinary process. The N.F.L. Players Association can appeal Robinson’s decision, and that appeal would be heard by Goodell or a person of his choosing.

During their inquiry, N.F.L. investigators interviewed 10 of the women who filed lawsuits against Watson, as well as other witnesses, including women who worked for the massage therapy group that is contracted with the Texans. The league first met with Watson last month for multiple days of interviews.

The Wall Street Journal reported last week that the N.F.L. based its case for a lengthy suspension of Watson on five women’s accounts that the league believed had the strongest evidence, including contemporaneous corroboration. A detective who led Houston police’s investigation of Watson said in a deposition for the civil lawsuits that out of the 10 criminal complaints filed against Watson, the strongest evidence came from the cases of Ashley Solis — Watson’s first accuser — and a woman who has not been publicly identified, who said that Watson ejaculated on her in their second massage appointment.

Both women met with N.F.L. investigators and are among the four civil plaintiffs who have not settled with Watson.

Solis’s lawsuit alleged that Watson purposely touched her hand with his erect and exposed penis in a March 2020 massage. Watson said in a deposition in the case that he apologized to Solis via text message after their appointment for her feeling uncomfortable, and went on to describe her as “teary-eyed” at the end of the massage, though he said he did not know why.

A woman Solis worked with also reached out to a veteran massage therapist on Facebook the day after Solis’s session with Watson, writing that her colleague had been “solicited” by a professional athlete and didn’t know what to do.

The second plaintiff, the woman who also filed suit against the Texans, massaged Watson twice in separate appointments at her mother’s house in Manvel, Texas, a Houston suburb, in November 2020. She claimed that Watson ejaculated on her in the second massage and asked to schedule another appointment with her for later that same day. She agreed but then canceled shortly thereafter, text message records show. The woman ignored further attempts by Watson to contact her and eventually blocked him.

That woman told a friend who played in the N.F.L. about her experience with Watson. She asked for advice since she was just starting out as a massage therapist and she had mutual friends with Watson. Speaking under condition of anonymity to protect his privacy, the player confirmed that she reached out after the massage and said that she had felt uncomfortable during the session. He said he told her if she did not feel comfortable, she did not have to work with Watson again.

He said he spoke with N.F.L. investigators as a contemporaneous witness.

According to a person who has reviewed the N.F.L.’s briefing materials, one of the five accounts the league asked the disciplinary officer to consider was from a woman who told Sports Illustrated about her experience with Watson. In their November 2019 massage appointment, the woman said Watson purposely exposed himself, told her she could move his uncovered penis, and began thrusting his pelvis in the air after developing an erection.

She told the therapist who set up the appointment, and later, when Watson tried to book with her again, she told him in a message that he had made her uncomfortable.

The woman did not file a lawsuit or a police report, and according to her lawyer, did not participate in the N.F.L. investigation. League investigators do not have subpoena power, so their inquiry relies on witnesses participating voluntarily and on acquiring evidence collected in the criminal or civil proceedings.