At first, U.S. Marine Phillip Bushong didn’t realize he had been stabbed. When he saw blood on the sidewalk beneath him, he called out to one of his friends nearby, thinking the friend was hurt.

Seconds later, Bushong, 23, who had been a lance corporal for two years, fell to the ground as his friends rushed to his side. They held his hand and applied pressure on the wound as they waited for police officers and paramedics to arrive. Bushong died minutes later.

The young man’s last minutes were recounted Tuesday in D.C. Superior Court during the second-degree murder trial of Michael Poth, 21, a fellow Marine charged in the April 21, 2012, attack.

One of Bushong’s friends testified that Poth used a slur against homosexuals and confronted Bushong and his friend outside a popular restaurant near Capitol Hill’s Barracks Row just after 2 a.m.

Nishith Pandya, 29, a congressional staffer, calmly told the jury that Poth and Bushong got into an argument and called each other a “boot” — a Marine term to describe a poor Marine or someone fresh out of boot camp. Pandya said he saw Poth reach over as the men were squaring off and “slap” Bushong in his chest. The slap was actually a stabbing, prosecutors have said.

In video footage from a nearby security camera, Poth is seen backing away from the camera angle as Bushong continues to lunge in his direction. Pandya said he shouted to his friend that he was bleeding. Bushong insisted that Pandya was hurt.

“It’s not my blood. I think it’s yours,” Pandya recalled saying.

Then Bushong looked down and agreed. “I think it is,” he said, according to Pandya.

The video then showed Bushong falling over out of the camera’s view.

Bushong’s family members, including his parents, wiped away tears in the courtroom. One juror covered her mouth.

“I rolled him over and applied pressure until police arrived,” Pandya said, his voice shaking.

There was no sound in the video, which showed Poth, smoking a cigarette, walking toward Pandya and Bushong. He kicked over a sidewalk billboard and had earlier kicked over a planter, according to testimony. One Marine, who encountered Poth earlier that evening, testified that Poth had been drinking and was carrying a small, folding knife when he encountered the two men.

Bushong and Pandya had also been drinking that evening with a group of their friends before Poth walked up to them as they stood outside the restaurant on Eighth Street SE.

Pandya testified that neither he nor Bushong struck Poth. Poth’s attorney, Bernie Grimm, argued that Poth was only protecting himself from the two men, who were attacking him and who were nearly a foot taller than his 5-foot-7, 140-pound client.

Assistant U.S. Attorney Michael Liebman said military officials had initiated an “other than honorable” discharge of Poth several months before Bushong’s slaying.

Poth had tested positive for using synthetic marijuana and had verbally assaulted other soldiers. But at the time of the attack, Poth was living in a Marine barracks.

Pandya, who told the jury he was gay, said he had no idea how Poth knew his sexual orientation when he made the slur against homosexuals. Pandya said he and Bushong were platonic friends.

Grimm tried to attack Pandya’s credibility. He reminded Pandya that minutes before the altercation, Bushong was ejected from the restaurant for being loud and boisterous and that Pandya had initially misidentified his friend’s attacker when he talked to detectives.

Pandya said Bushong, who was in the Marines Color Guard, was scheduled to be discharged from the Marines less than a week after the incident.

The trial, before Judge Russell F. Canan, could be concluded by the end of the week.