Former Trump campaign chairman Paul Manafort’s recent guilty plea suggests the Mueller probe “is in the fourth quarter,” former FBI Director James Comey said Wednesday.

“The way you normally do investigations is you work from the bottom up, and so they’re getting pretty high,” Comey said in an interview with St. Louis’ NPR affiliate.

“But again, the reason I’m hesitant to even say that is [because] Bob Mueller’s conducted his investigation like a pro – you know nothing about it except through his public filings, and that’s the way it’s supposed to be. And so I can’t say with certainty where he is.”

Comey added that there is an argument to be made “that the conviction — the plea and cooperation by Paul Manafort – may represent that we’re in the fourth quarter.”

Manafort pleaded guilty on Sept. 14 to conspiracy charges related to his work for the Ukrainian government several years before joining the Trump campaign. As part of the plea deal, Manafort agreed to cooperate with the special counsel’s office. (RELATED: Manafort Cooperating With Mueller After Plea Deal)

Manafort was scheduled to go to trial in Washington, D.C., in the case. He was convicted in federal court in Virginia on Aug. 21 on tax fraud and bank fraud charges related to his Ukraine work.

It is still unclear whether Manafort is providing information about the Trump campaign or about other matters.

The White House has said it is not concerned with Manafort’s plea agreement, saying that he has nothing damaging about Trump to offer prosecutors.

Comey, who was fired as FBI chief on May 9, 2017, oversaw the first 10 months of the FBI’s collusion investigation. Mueller took over that probe, and is reportedly also investigating whether President Donald Trump obstructed justice by firing Comey.

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