The 24-year-old man clashed with Jackson attorney Thomas Mesereau Jr., who tried to highlight inconsistencies between the story that the witness told on the stand and his earlier accounts.
"I don't mean to sound like I'm wasting your time," he told the lawyer at one point. "It's hard being up here."
"Just answer my question," said Mesereau.
The witness, the son of a former Jackson housekeeper, was called by the prosecution on Monday in an effort to show Jackson has a pattern of inappropriate behavior with boys. Jackson is on trial on charges of molesting a 13-year-old cancer victim in 2003 at his Neverland ranch.
The housekeeper's son received $2.4 million from Jackson in 1994 and no criminal charges were filed. The jury was told of the settlement but not the sum. The boy's attorney acknowledged the terms involved no admission of wrongdoing by Jackson.
On Monday, the young man said Jackson twice touched his crotch over his clothes and once reached under his clothes and touched his genitals during tickling games when he was 7 to 10 years old. He also said that in the first two incidents Jackson stuck $100 into his clothes.
"We were tickling. He was tickling and I was laughing and the — it was, he was — he was tickling me in the...," the witness said before asking the judge for a break. He wiped his eyes and drank some water.
"He was tickling me. I was wearing shorts again. ... He reached on my leg and I'm still laughing and he reached up to my — privates," the witness said.
As he began to describe the alleged molestation he apologized to prosecutor Ron Zonen for his halting testimony and said: "This took a lot of counseling to get over, just to let you know."
He said he told no one until 1993, when detectives investigating another boy's allegations came to him. That interview was followed by others in 1994 and in October, November and December 2004.
CBS News Legal Analyst Andrew Cohen said the witness presented "damning details" without the excess baggage the accuser brought to the stand. His credibility wasn't in question, so Cohen said he put Jackson's defense in a hard place.
"This is precisely the sort of testimony that Jackson's attorneys feared when they fought so hard last week to convince the judge that it shouldn't be a part of this case," Cohen said. "They knew it would be devastating, and hard to overcome, and it was and is."
Under cross-examination Tuesday, he acknowledged that in his 1993 interview he initially said Jackson did not molest him. Mesereau asked whether investigators became aggressive and began calling Jackson a "molester" and cursing.
The witness said he did not remember details of the interview.
"It was only after you were pushed real hard by the sheriffs that you began to say anything like that," Mesereau said.
The witness said he could not remember who was present or what was said in most of the interviews.
He also contradicted himself on a couple of points. Under questioning by Mesereau, he said Jackson would give him money whenever he read a book or got an A. Under questioning by one of the prosecutors, he said that did not happen.
Mesereau confronted the witness with a statement he made during one of his interviews in which he said: "They made me come up with a lot more stuff. They kept pushing. I wanted to hit them in the head."
The witness said he did not remember the statement.
Mesereau showed him a transcript and asked if that refreshed his recollection.
The witness said no.
"Do you remember anything you said in that interview?" asked the attorney.
"No," said the witness.
The witness also pleaded a poor memory when asked about whether his claims resulted in a criminal case. "I don't know much. I don't watch the news," he said.