(CNN) -

Defense attorney Kirk Nurmi will have to stay on and advise Jodi Arias as she represents herself at her penalty phase retrial in September, Judge Sherry Stephens has ruled.

Nurmi asked the judge last week to let him off the case for good now that Arias has decided to represent herself. He said that since he's only acting as an adviser, his role would not be as crucial as it was before, when he was Arias' lead attorney. Arias also told the judge during the hearing that she would stop representing herself if Nurmi were allowed to withdraw.

Stephens, a Maricopa County, Arizona, Superior Court judge, took the matter under advisement and then added a note later to the court minutes -- or record of the hearing -- from August 13 stating that "It is ordered denying Advisory counsel Kirk Nurmi's Motion to Withdraw."

In May 2013, a jury found Arias guilty of first-degree murder in the brutal 2008 slaying of her ex-boyfriend, Travis Alexander.

Although jurors were unanimous in their decision to convict Arias, they could not come to an agreement on whether to sentence her to the death penalty or life in prison. A new jury, tasked with making a decision regarding sentencing, will be selected for Arias' retrial, which is scheduled to begin September 8.

Arias will be presenting her case to that new jury -- for now, at least. If Arias decides that she is in over her head, the judge said, she will allow the convicted killer one last chance to change her mind and retain counsel again.

On August 11, Arias appeared before the judge for the first time since deciding to represent herself and asked the judge to delay the retrial so she could have more time to meet with witnesses. Her motion to continue will be heard Friday.

Arias and her defense attorneys, Nurmi and Jennifer Willmott, have made attempts in the past to sever their relationship with each other.

In November, Stephens denied a request from Arias asking that Nurmi be tossed from the case. In a 12-page handwritten letter to Stephens, Arias said she hadn't spoken with Nurmi for months and claimed that he had "little to no tolerance for my emotional and psychological shortcomings."

The judge also denied requests from Nurmi and Willmott, who wanted off the case in May 2013 after Arias gave an interview to Phoenix TV station KSAZ following the jury's guilty verdict. Arias told KSAZ's Troy Hayden she would "rather get death than life."

The attorneys asked a second time to withdraw from the case during the penalty phase of the trial, after their request for a mistrial was denied. They requested a mistrial after a defense witness, Arias' childhood friend Patricia Womack, declined to testify, saying she received multiple death threats.

If the new jury in the retrial cannot reach a unanimous verdict, Arias will automatically get life in prison. However, the judge will decide whether Arias will get life without parole or life with the eligibility of parole after 25 years.