McQueary, when pressed by Rominger, also said he "made sure Coach Joe knew it was sexual," referring to head coach Joe Paterno.
Rominger tried to show that McQueary had changed his story about what he saw to the people he told.
McQueary, raising his voice on the stand at Rominger, said that if his father's friend contradicted McQueary's account of events, he "would not call him a liar."
McQueary told the lawyer that Rominger was "playing semantics." When asked if he was sure Sandusky saw him in the locker room that night, McQueary said, "I'm a tall man," and "a big red-haired guy, most people see me wherever I go," causing laughter in the courtroom.
Rominger pressed McQueary for details about what he saw, confirming that McQueary never saw genitals or insertion, but McQueary said, "There's no way his genitals were not pressing up against the boy's rear end."
His testimony was the third major account of sexual abuse heard during the trial, and followed the halting, crying testimony of the man known as "Victim 1" this morning, the 18-year-old man who launched the sex abuse investigation into Sandusky.
The teenager wept on the stand today and brought some jurors to tears as he recalled the first time the former Penn State coach allegedly performed oral sex on him, when he was about 12 years old.
"After rubbing, cracking my back and rubbing his hands down back of my shorts, and the blowing on the stomach," he said, pausing to cry, "he put his mouth on my privates. I spaced, I didn't know what to do. With all the thoughts running through my head, I just kind of blacked out and didn't want it to happen. I was froze," he said.
The man, whom ABC News is identifying only as Victim 1 because he's an alleged sex-crime victim, reported the alleged sexual abuse to his mother and his high school in 2008.
The recent high school graduate was the second accuser to testify during the trial, which began Monday in Bellefonte, Pa., 10 miles from Penn State University.
He described meeting Sandusky through Sandusky's charity for underprivileged boys, the Second Mile, and spending time with Sandusky playing sports, doing activities, and sleeping over his house.
Victim 1 described staying In Sandusky's basement bedroom, where a water bed and television were sequestered away from a pool table. It was there that Sandusky began abusing him, he said.
Jury members placed their hands over their mouths or wiped tears away from their eyes as the man testified that Sandusky forced him to perform oral sex.
"lt was back cracking, rolling around in bed, back massages, hands down back of my shorts. The same thing," he said, pausing to cry. "Except this time he sat there and he looked at me and said something along the lines of, 'It's your turn,' and he made me, he made me put my mouth on his privates. In the basement room."
Joseph Amendola, the defense attorney for Sandusky, tried during cross-examination to pick through the accuser's account of events, showing that he told investigators with Children and Youth Services and the state police different timelines for when the oral sex abuse began and ended, and showing that he didn't even mention oral sex to investigators until about eight months into the investigation, when troopers told him there were other young people with similar claims.