(Photo : Allison Shelley/Getty Images)
Commander of U.S. Central Command, Gen. Lloyd Austin II, holds a media briefing on Operation Inherent Resolve, the international military effort against ISIS on October 17, 2014 at the Pentagon in Washington, D.C.

Democrat Joe Biden is set to nominate retired Army General Lloyd Austin as his defense secretary, sources familiar with the matter confirmed.

If Austin gets confirmed to serve as defense secretary under the Biden administration, he could be the first Black person to lead the Pentagon. He could be leading the country's 1.3 million active-duty troops.

Formerly, he served as the first Black chief of the U.S. Central Command from 2013 to 2016 and led the American military effort in Iraq, reported New York Times.

Politico first reported about Austin's nomination. 

Biden Under Pressure to Nominate a Black Defense Secretary

The Hill said in its report that Biden had been under pressure to select a Black defense secretary as some Black leaders said he was falling short on diversity in his Cabinet.

Two of the other "Big Four" Cabinet positions were given to white people: Anthony Blinken as secretary of State, and Janet Yellen as Treasury secretary, reported The Hill.

Austin's nomination could come as soon as Tuesday.Only the position of attorney general remains open among the said Big Four positions after Austin was chosen.

The person who would occupy that position could be named this week as well, said Market Watch. 

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Biden's transition team and Austin declined to comment to Politico.

Michele Flournoy, Jeh Johnson Also Considered as Defense Secretary

Michele Flournoy, who served as undersecretary of Defense for policy, was first considered the top pick as Biden's defense secretary. But competition started to heat up as Biden dragged on naming his choice, and then came pressures to have a Black nominee.

Flournoy could have been the first female defense secretary, but her name was notably absent when Biden rolled out the key members of his national security team two weeks ago.

Former Homeland Security Secretary Jeh Johnson was also considered for the job, according to several people familiar with the discussion.

The Congressional Black Caucus even threw their support Johnson's way. However, there were lingering concerns about Johnson's tenure in the Obama-Biden administration that improved Austin's standing.

"General Austin is a southerner, has impeccable credentials given his military career and would be an outstanding secretary for the department," Rep. Bennie Thompson, a member of the Caucus, told Politico.

Apart from news that Johnson was also in the running to be attorney general, he also faced concerns from progressives about his record in the Department of Homeland Security.

Johnson was said to have expanded family detention, accelerated deportations, and approved drone strikes killing civilians.

Flournoy and Johnson already received word that they were not chosen, The Hill's source said.

Defense Secretary Pick Austin Also Holds Baggage

In his choice to have Austin for the position, Biden chose a barrier-breaking four-star officer. But while Austin is known for his battlefield command, he isn't as prominent in political instincts.

At times, the retired general had come of congressional hearings, like that in 2015, where he acknowledged that the Defense Department's $500 million programs to combat Syria had "gone nowhere." 

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He was shredded by lawmakers for the said failure to train moderate fighters to battle ISIS that only produced "four or five" fighters.

Most importantly, Austin lacked the seven-year cool off period required by the law to serve as defense secretary. Austin retired in 2016, so he's about three years short of the requirement.