Groundskeeper Willie Leak is approaching his 50th anniversary working at RFK Stadium. (Michael S. Williamson/The Washington Post)

Most mornings, Willie Leak arrives at RFK Stadium in his Grand Cherokee between 6:30 and 7. The drive from Bladensburg takes 10 minutes. He strides past the security office and through Tunnel B, which empties into the southern corner of historic grounds.

Leak walks the field and inspects the grass, identifying rough patches and assessing water levels.

“Most of it is old habit,” said Leak, 69. “It tells me what my day is going to be about.”

This is his workplace. Really, though, it’s home.

RFK’s gates swung open 521 / 2 years ago. A North Carolina transplant seeking a paycheck after high school, Leak reported for his first day of work on East Capitol Street 50 years ago next month.

He swept spilled popcorn and trampled beer cups for $1.25 an hour after Senators and Redskins games before joining the grounds crew and ultimately becoming head groundskeeper in the mid-1990s.

Yes, he is a real-life Groundskeeper Willie. “I’ve heard that one a few times,” he said, chuckling at the reference to the cantankerous character from “The Simpsons.” Leak, conversely, is a quiet caretaker.

“He has seen everything here and is unfazed by it — he is just focused on the job,” said Erik Moses, senior vice president at EventsDC, which manages RFK. “Nowadays, people would want to Instagram everything they see. He’s all lunch-pail.”

Leak has not kept a tally of sporting events he has worked, but a rough estimate nears 2,000. During his tenure, the Senators played eight seasons at RFK and the Nationals three. The Redskins toiled for 33, and on the night of March 8, D.C. United will begin its 19th.

There were the USFL’s Federals, NASL’s Whips, Diplomats and Team America, and ASL and APSL’s Dips. There was Mia Hamm and the Washington Freedom women’s soccer team, the World Cup, Olympic soccer, Soccer Bowl, three MLS Cups, the Women’s World Cup and U.S. national team matches.

There were MLB and MLS all-star games, George Washington University football, the Military Bowl, high school football championships and a Riddick Bowe bout.

He crossed paths with Vince Lombardi, who closed his Hall of Fame coaching career with the Redskins in 1969, and witnessed Joe Gibbs’s glory years. He worked in the shadows of baseball icons Ted Williams, the Senators’ boss from 1969 through 1971, and Frank Robinson, who guided the Nats in 2005-06.

He did not have much interaction with the athletes and coaches, although Williams would initiate chatter, and Senators catcher Paul Casanova became a friendly face.

Beyond sports, Leak was on location for rock ’n’ roll royalty: The Beatles, Rolling Stones, The Who, Elton John, Michael Jackson, Bruce Springsteen, Madonna, Pink Floyd, U2 and Grateful Dead. There were presidential first pitches, a religious rally, mass wedding and the stadium’s 1969 renaming following Robert F. Kennedy’s assassination. (In October 1961, the venue had been christened D.C. Stadium.)

Leak has not seen all of the acts and games; once the field is prepared, he typically retreats to the back tunnels or his third-level office.

“Before game time was our time, maybe 7:30 in the morning until 10 or 11,” he said of prepping for Redskins games. “It was our field. After that, it was their field.”

Fans have staked claim to the field, as well: In the ninth inning of the Texas-bound Senators’ farewell game in 1971, hundreds jumped the barriers, ran the bases and yanked up grass for souvenirs. Leak and his colleagues watched helplessly.

In early 1992, after a Redskins touchdown against the Atlanta Falcons secured a berth in the NFC championship game, fans celebrated by flinging seat cushions into the end zone. The crew gathered them like spilled playing cards.

The most challenging assignment: Between 2005 and ’07, when United and the Nationals shared the stadium, the grounds crew would transform a soccer field into a baseball diamond overnight and vice versa.

Does Leak know every nook and cranny of the creaky structure? “Yes sir, unless they’ve added something new,” he deadpanned.

He was briefly married long ago — “Stayed away too long to be married. Always at the ballpark,” he said — and has two daughters. His staff is family: All three understudies have been with him for at least 12 years, one for decades.

“He amazed me,” said Tony Burnett, a former RFK head groundskeeper who was Leak’s boss. “He could work four or five days without sleep. Could always depend on Willie.”

Burnett, 69, and Leak grew up together in Durham, N.C. Burnett and his older brother began working at RFK in 1962, and except for a three-year service in Vietnam, Burnett reported to RFK for 40 years before retiring. In 1964, he suggested Leak join him in Washington. Cleaning duty was seasonal, so Leak was not on the regular payroll until he moved to the grounds crew in 1969.

He has been on the job since, growing into an expert on laser grading, shade-tolerant turf and the rhizome structure.

“Every time I see Willie, I say, ‘Hey man, when are you going to quit?’ ” said Burnett, who lives in Temple Hills. “He loves what he is doing.”

Leak figures to work full-time two or three more years before beginning to reduce his workload. Until then, he will continue to make early-morning rounds.

“I have spent some time here,” he said, adjusting his baseball cap. “I mean, I have put in some hours.”