During a trial in a Virginia courtroom in September over Google’s dominance in advertising technology, concepts and phrases like a “second-price auction," “demand-side platforms” and “header bidding” repeatedly came up.

Judge Leonie Brinkema of the U.S. District Court of the Eastern District of Virginia, who was presiding in the antitrust case, often grasped within minutes the obscure mechanics of placing ads online. She also pushed lawyers to move on when they slowed down the proceedings with objections, or when witnesses repeated things she had already heard.

“Let’s go,” Judge Brinkema said again and again.

The trial lasted just three weeks. In contrast, a landmark antitrust trial last year over Google’s search dominance took 10 weeks. Another antitrust trial over Google’s app store policies, a case brought by Epic Games, spanned a month. The Microsoft antitrust trial in the late 1990s lasted more than eight months.

Now Judge Brinkema, 80, is moving the Google ad tech case to its next phase in the federal court where she works, which is known as a “rocket docket.” On Monday, she plans to hear closing statements from the Justice Department and a group of states, which brought the ad technology case, and from Google’s lawyers. Earlier this year, she told lawyers she would use closing arguments to answer her remaining questions before she issues her decision, which is expected in the coming months.

Her ruthless efficiency has made the case one of the speediest monopoly trials in recent decades. That could swiftly add to Google’s challenges, since Judge Brinkema could order the Silicon Valley giant to sell many of its ad tech assets if she finds that the company subverted competition. The ad-tech division generated $31 billion last year for Alphabet, Google’s parent company, or 10 percent of its sales.