"'It’s fantastic,' Mr. Trump said about his rapport with Mr. Rosenstein when a spokesman told him The Wall Street Journal was seeking a comment."

"'We have great relationship. Make sure you tell them that.' Mr. Rosenstein declined to comment for this article. In a statement, a Justice Department spokeswoman said he has a 'productive working relationship' with Mr. Trump. As the Mueller investigation proceeds, their relationship may sour. Mr. Trump has consistently called it a 'witch hunt,' and Mr. Rosenstein has said protecting the probe is a priority. But the rapprochement may signal that, despite the president’s public statements, the investigation isn’t in immediate danger of being halted. Senior White House officials privately praise Mr. Rosenstein’s handling of demands by congressional Republicans to share internal documents on the Federal Bureau of Investigation’s investigations of Hillary Clinton’s email server and any Trump campaign contacts with Russia. Some Trump allies—such as Reps. Mark Meadows (R., N.C.) and Jim Jordan (R., Ohio)—accuse Mr. Rosenstein of stonewalling, but White House officials say they view their effort to impeach Mr. Rosenstein as a sideshow. Indeed, the president has recently come to rely on Mr. Rosenstein, the No. 2 at the Justice Department whom the White House increasingly views as the No. 1, given the president’s disenchantment with Attorney General Jeff Sessions over his decision to recuse himself from the Russia investigation because he served on the Trump campaign...."

From "'It’s Fantastic!' Trump Warms to Rosenstein/Nearly fired by the president, the No. 2 Justice official—the man in charge of the Mueller probe—builds a rapport" in The Wall Street Journal, which seems available without a subscription. I got in anyway.