Los Angeles (CNN) -- The involuntary manslaughter trial of Dr. Conrad Murray, charged in the death of Michael Jackson, will be delayed until September, a judge decided Monday.
The defense had asked for just two weeks to find and prepare new medical experts to counter new experts recently added by the prosecution.
Murray, who was Jackson's personal doctor, is accused of causing his death on June 25, 2009, while giving him a surgical anesthetic.
Los Angeles County Superior Court Judge Michael Pastor, during a Monday morning hearing, asked Murray if he agreed with a delay.
"I believe it is in the best interest of all parties involved," Murray told the judge.
Jury selection, which began in late March, was expected to conclude this week. Opening statements and testimony had been schedule to begin next Monday.
"We have to pause for a moment and take a breath," Pastor said. "All of us should be ready before we go into further proceedings with a jury." He said the jury selection will begin around September 8, and opening statements could begin on September 20.
The delay is likely to mean the 171 potential jurors already "hardship qualified" for a two-month trial will be dismissed and the jury selection process will start from scratch.
"If it means saying 'thank you' to the prospective jurors, then I think that's the preferable approach," the judge said.
A delay, however long, would be expensive for the cash-strapped court system. Pastor said there had been a "massive investment of time and money" put toward the trial.
But, he added, "The interests of justice trump everything."
The possibility of a delay was raised Friday when Pastor ruled prosecutors could call new expert witnesses, including one who would testify that there was no way Jackson could have self-ingested the drug that the coroner said killed him.
Defense lawyer Ed Chernoff said he consulted with Murray after that hearing and they agreed they needed more time to prepare their expert testimony to counter the new prosecution experts.
"This is precisely the matter I fully expected that was going to happen when the defense said it wanted to go in 60 days," Pastor said.
Murray invoked his right to a speedy trial after January's preliminary hearing in which the prosecution's expert witness admitted he made a math mistake that supported the defense theory that Jackson may have given himself the fatal dose of propofol.
Propofol is a surgical anesthetic that the Los Angeles coroner ruled killed Jackson, in combination with several sedatives found in his blood.
"I actually made a mistake on that," Dr. Richard Ruffalo testified during cross-examination, referring to his calculation of the levels of drugs in Jackson's stomach fluid.
Murray's lawyers suggest a frustrated and sleepless Jackson may have poured the surgical anesthetic propofol mixed with lidocaine into his juice bottle while the doctor was out of his bedroom.
A new expert approved by Pastor on Friday will testify that he "concludes it was impossible for Michael Jackson to orally ingest" the fatal drug, prosecutor David Walgren said.
"Super expert Dr. Ruffalo prepared a 60-page report," Defense lawyer Michael Flanagan said in court Friday. "We got ready on that, but now the trial in this case will look nothing like the preliminary. I bet you they're not going to call Ruffalo."
The prosecution said the defense is always welcome to call the former prosecution expert.
"They are not calling their original 11 experts," Flanagan said. "They've got three brand new ones, which requires us to prepare all over again for these new theories and justifications of these theories."
The new experts will present "more detailed analysis, but not a new theory," Walgren said.
In Session's Beth Karas contributed to this report.