Two police officers involved in the mistaken arrest of former tennis pro James Blake, including one who tackled him to the ground, will face an administrative trial after the city's police watchdog substantiated Blake's excessive-force complaint.

The Civilian Complaint Review Board's executive director, Mina Malik, said in a letter sent to Blake that investigators had substantiated complaints he made after his Sept. 9 arrest alleging that Officer James Frascatore used excessive force and Detective Daniel Herzog abused his authority.

Surveillance video showed Frascatore approaching Blake in front of a Manhattan hotel, grabbing his arm and roughly taking him to the ground. Police said Blake, who had ranked as high as No. 4 in the world before retiring from tennis after the 2013 U.S. Open, had been mistakenly identified as being part of a cellphone fraud scheme. Frascatore had mistaken Blake for a suspect who looked like him, police said.

Mayor Bill de Blasio and police Commissioner William Bratton have apologized to Blake, who has said he believes Frascatore should be fired.

"It is my understanding that these officers now face an administrative trial for their roles in the respective offenses," Blake said Wednesday in a statement that accompanied the CCRB letter. "I have complete respect for the principle of due process and appreciate the efforts of the CCRB to advance this investigation."

Frascatore, who has been with the New York Police Department for about four years, had been named in several civil rights lawsuits alleging excessive force. He was placed on desk duty after the encounter with Blake.

A departmental trial could end in disciplinary action or termination.

Malik said Blake's complaint had been resolved in less than 30 days, but she declined to provide further information about the probe, citing state privacy laws.

"Our commitment remains to be a fair and vigilant resource for all people who have complaints about police misconduct, and to judge the cases based on thorough, even-handed investigations which serve the public and officers alike," she said.

The head of the largest police officers' union said he wasn't surprised to hear that the watchdog group, which he described as "cop-hating," substantiated Blake's allegations. Patrolmen's Benevolent Association President Patrick Lynch said it was clear Frascatore did not intend to harm Blake.

''He used an acceptable technique to gain compliance during a complex ongoing operation in a manner that did not compromise the simultaneous arrest being made a short distance away," Lynch said. "An objective review of the facts will vindicate the officers involved."