Darrell Waltrip made a second career out of never running short of words. Three Cup Series championships put him in the record books, and his long run as a Fox broadcaster made him one of the most recognizable characters NASCAR has produced, the man whose instant verdicts on a race often became the way people remembered it. On Wednesday, according to a statement from his family, Waltrip, 79, was diagnosed with frontotemporal degeneration and will be stepping further away from public life. The family said the disease was likely complicated by possible chronic traumatic encephalopathy, which they linked to injuries from his 29-year racing career, and that his symptoms so far have been minor.

A man who seemed most at home in front of a microphone is leaving it, and that loss belongs to him and his family before it belongs to anyone else. The news also sends memory back to the hardest afternoon of his broadcasting life, the 2001 Daytona 500, when the story on the track stopped being a race.

Most of this week's tributes file Waltrip under two headings, champion driver and booth entertainer, and the filing skips the afternoon his job turned into something else. NASCAR's safety reforms after Dale Earnhardt's death usually get told as a story about rulebooks and equipment. That version leaves out the people who had to describe the loss while it was still unfolding. Waltrip was one of them. He was a former driver and a longtime friend of Earnhardt, and he was in the broadcast booth that day, so the witness and the narrator were the same man. His family's statement gives that overlap a second edge this week. The danger he talked about on air was, by their account, a danger he may also have carried home.

Sundays Will Never Be the Same, written with Nate Larkin, opens at the final laps of the 2001 Daytona 500, retold moment by moment from the broadcast position. From there it follows the scramble to the trauma center and the weeks after, which is the stretch most retrospectives skip. A traveling sport gives grief no days off. The next race stays on the calendar, and the people who knew Earnhardt have to keep showing up for work, some of them on camera, some of them expected to sound like themselves. Then Waltrip backs up a long way.

The middle of the book traces his relationship with Earnhardt from early encounters through a decades-long friendship he describes as often fraught. It widens into profiles of the figures who shaped the sport, including Bill France, Junior Johnson, Cale Yarborough, Bobby Allison, and Richard Petty. Those portraits give the Daytona chapters their weight. After enough time among hard, stubborn men who treated danger as part of the job, Earnhardt's death stops looking like a freak event and starts looking like the bill for a long-standing habit. You come away understanding how a sport run by people like this could take so long to disagree with them, because for most of its history the risk was the point, or at least the price of admission everyone had agreed to pay.

The book also recounts the safety reforms and industry changes that followed, a subject the memoir form handles poorly. Waltrip raced inside that culture and prospered from it, and a memoir rarely cross-examines its own author. If you want a rigorous account of why the sport waited as long as it did, or who pushed back on change, you will probably need a second source. I also suspect the fraught friendship arrives a little sanded down, as friendships tend to when the survivor holds the pen and the other man cannot answer. The humor is the reason to read it anyway.

The book is candid and often funny, stocked with locker-room stories, and it keeps circling the strange strain of a man paid to be lively describing the day his sport lost its biggest star. Reading it now, after the family's announcement, the jokes carry a small ache. They were how he coped, and how he kept a television audience company through a terrible week. That instinct, to keep talking so nobody watching feels alone, is the most human thing in the book.

Waltrip spent years telling millions of people what they were looking at, fast, with a grin you could hear through the television. Now the public talking stops, and the quiet is his and his family's to keep. If you want a few hours with him on his own terms, Sundays Will Never Be the Same is a warm place to spend them. It is partial and loyal, the way memoirs usually are. It is also the record of a man who had to find words on the day a friend died on the track below him, found them, and kept working through the weeks that followed.