Maryland offensive lineman Jordan McNair, who died last month, appeared to have suffered a seizure and was “unable to control” his breath after the football practice that led to his hospitalization, according to 911 tapes obtained by The Baltimore Sun.

An unidentified caller described McNair’s breathing problems to a Prince George’s County emergency dispatcher just before 6 p.m. on May 29, according to an audio copy of two calls and an incident report released by the county’s Office of Homeland Security after a public-records request.

Medical personnel arrived at Gossett Football Team House in College Park less than five minutes after the call was logged, the incident report shows.

In a second call, a first responder reported to dispatchers that McNair had had a seizure. McNair arrived at Washington Adventist Hospital, in nearby Takoma Park, at 6:36 p.m., according to the county’s report.

The records expand on the chronology university officials and McNair’s parents have provided in the wake of his June 13 death. In a news conference last month, Terps athletic director Damon Evans said McNair, 19, had difficulty recovering after a supervised late-afternoon workout that included 10 110-yard sprints, described as a “baseline” conditioning activity.

The university disclosed last week that the workout also included position-specific drills.

After the workout, McNair was taken to the team house, where the football program is headquartered, for further observation and care, Evans has said. McNair died two weeks later.

The state medical examiner’s office did not perform an autopsy, and the university has not disclosed the cause of McNair’s death, citing privacy for the family. But the website of a foundation his parents launched in the former McDonogh star’s honor said it was heatstroke, which can cause seizures.

The university has hired Walters Inc., an athletic training consulting firm, to conduct an external review of the team’s protocols in connection with McNair’s death. The review was set to begin late last month and could take up to 90 days. A university spokesman on Wednesday declined to comment further on the incident.

jshaffer@baltsun.com

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