Two detectives injured in a gun battle yesterday in the Bronx had to undergo an alcohol breath test to make sure they were fit for duty at the time, police officials said.

It was the first time the breath test policy was invoked since it went into effect Sunday, and it set the stage for a fight between the police department and unions.

Detectives William Gonzalez and Daniel Rivera, both with nearly 20 years on the force, sustained minor gun wounds after engaging in a shootout with a suspect sought for a July bodega shooting. The plainclothes detectives, of the Bronx violent felony warrants squad, later submitted willingly to breath tests by internal affairs officers. They passed.

Commissioner Raymond Kelly introduced the policy for police officers that fire at suspects as a response to the shooting of Sean Bell last year in Queens.

The president of the Detectives Endowment Association, Michael Palladino, said yesterday’s incident could become a part of a federal court challenge to the policy. “They put their life on the line, they got injured, they were shot at. It’s degrading and it’s demoralizing to have these officers have to undergo a Breathalyzer,” Mr. Palladino said, referring to a name brand of the alcohol test.

At about 5:30 a.m., Detective Rivera, 41, and two officers approached the front door of a Webster Avenue apartment building they had been observing for two days, while Detective Gonzalez and another detective circled around to the back, officials said. A woman answered the door as the suspect, identified as Jermaine Taylor, 18, pulled an airconditioner from a window and jumped two stories into a narrow alley.

Police officials later said they found a surveillance system in the apartment that allowed residents to monitor the building’s front entrance.

Police said Detective Rivera raced to the back of the building to help Detective Gonzalez and the other detective, Thomas Murphy, as Mr. Taylor allegedly began shooting at the detectives.

Mr. Taylor fired at least six shots with a 9-mm Italian semi-automatic pistol, officials said. Detectives Gonzalez and Murphy each fired five shots, emptying their revolvers, while Detective Rivera, who showed up seconds later, fired three from his semi-automatic.

Police said Mr. Taylor’s middle right finger was severed by one of the police bullets, likely ending the gunfight. Mr. Taylor’s gun was found with three live rounds unfired.

Detective Rivera was grazed between the eyes with a bullet, and Detective Gonzalez was hit in the right shin. Both were released after being treated at St. Barnabus Hospital.

Mr. Kelly and Mayor Bloomberg praised the wounded officers yesterday at a news conference.

“These are three very lucky detectives,” Mr. Kelly said.

Officials said the shooting was justified under official police guidelines.

Mr. Taylor fractured his pelvis during his fall and was treated at Jacobi Medical Center. He is being charged with attempted murder of a police officer.

Police said Mr. Taylor lived elsewhere in the Bronx, but had not been home since he was accused of shooting one person in the leg and another in the torso during a July incident outside a bodega at 320 Holland Ave.

Police found three pit bulls in the apartment, which they described as a flophouse with a stash of marijuana and clothing strewn about. The pit bulls had been using the bathtub as a toilet, police officials said, and were taken to Animal Care and Control.

Police said there were seven other people in the apartment at the time of the shooting, including an 11-year-old boy and his mother. Three men from the apartment were arrested, two on prior warrants and one for the marijuana.