As he walks down the curved, red tunnel that leads to the playing field, Joe Furin is recalling some of the historic grandeur of the Los Angeles Memorial Coliseum.

“The ’32 Olympics, Sandy Koufax, Jackie Robinson, the Fearsome Foursome — Deacon Jones, Merlin Olsen — everyone went down this tunnel,” he says.

But where the tunnel opens to reveal the 93-year-old stadium’s wide expanse, there is a slow but steady drip from the ceiling. Furin, the venue’s general manager, has been working hard to patch leaks like this one. “Knock on wood, we think we’ve identified them,” he says. But it’s still a work in progress.

In just six weeks, the Los Angeles Rams will take the field at the Coliseum. It will mark the end of the NFL’s 21-year, self-imposed exile from Los Angeles. It will also be the first time the Rams play a game at the venue since 1979 — the year they went all the way to the Super Bowl before decamping for Anaheim.

The Rams’ owner, Stan Kroenke, has announced plans for a $2.6 billion stadium complex at the Hollywood Park site in Inglewood, but it’s not slated to open until 2019. So for the first three seasons back in L.A., the Rams will be playing at the Coliseum, which was state of the art in 1923.

The facility is in such a state of decrep- itude that it’s hard to believe it can house an NFL team, even for a few years. The paint is fading and chipped. The concourse is narrow and cramped. The bathrooms are unrenovated. The seats are sun-bleached. Cellphone reception is poor. There are no luxury boxes or club suites, and few handrails. The electrical and plumbing systems need repair. The concession stands have no kitchens, so they don’t offer much more than hot dogs and nachos. There are leaks in the locker rooms.

“It doesn’t have all the modern amenities, which they’re in the process of addressing,” says Bruce Warwick, the Rams’ director of operations. “It has challenges, but it also has charm. It has history.”

The visitors’ locker room is especially tiny — supposedly due to the late Raiders owner Al Davis, who sought every tactical advantage for the home team. During preseason, when teams have 90-man rosters, it’s hard to imagine how they’ll all fit inside.

For the most part, the Rams are taking the stadium as is. But the NFL does have two major requirements that must be addressed before the Dallas Cowboys arrive for the first preseason game, on Aug. 13.

The first is security. The Coliseum will install metal detectors at all entrances, which will require pushing the fence line further away from the stadium; the trick is to do this without creating massive queues to get in.

The second issue is lighting. USC — the stadium’s primary tenant — was planning on upgrading the incandescent lights in 2017. But with the arrival of the Rams, the school decided to go ahead and get the work done. The LED lights going up now will be brighter — making games look better on TV — and more energy efficient.

But other problems — perhaps most significant, parking — will go unaddressed. The Coliseum routinely handles big crowds for USC Trojans games, but many of the attendees are students who walk to the stadium. The property has only 5,031 spaces for vehicles, and around 70,000 people are expected for a Rams game. So planners expect to have to find parking for 23,000 cars.

USC will open its garages, and there are private lots in the neighborhood. When the Raiders called the Coliseum home, residents offered fans parking in their driveways and on their lawns. Planners are also hoping attendees make use of the Expo Line train or Uber and Lyft. Still, parking promises to be a mess.

“It’s controlled chaos,” Furin says. “It is what it is.”

For a long time, the Coliseum was the major obstacle to NFL football returning to L.A. For a decade, the city’s political class favored it as the permanent home for a new football team, hoping that private investment would restore the aging public facility. The league played around with the idea, but too many people had serious reservations.

“Trying to put a new dress on an old hooker is not the way I want to go dancing,” Baltimore Ravens owner Art Modell told the Los Angeles Times in 2002.

The NFL finally dropped the idea of returning to the Coliseum for good in 2006. The Coliseum Commission — the public body that oversees the facility — had delayed making upgrades in hopes that a professional team would pay for them. But with the NFL out of the picture, the stadium was in a bind.

Through many years of neglect, the venue fell below the standards of even college football. The USC Trojans complained bitterly about the antiquated restrooms, the video boards, and the audio system. At one point, the school even threatened to relocate to the Rose Bowl.

To convince USC to stay, Pat Lynch, then the Coliseum’s general manager, agreed to put $60 million into renovations. But a deal for corporate naming rights for the stadium fell through, leaving the Coliseum Commission without the funds to pay for the upgrades.

Meanwhile, Lynch was pocketing funds on the side. According to prosecutors, he took $385,000 in kickbacks from the stadium’s janitorial firm. He later pleaded guilty to a conflict-of-interest charge, and was sentenced to probation. His right-hand man, Todd DeStefano, was charged with embezzlement and bribery for taking money from promoters who held concerts at the stadium. His trial is set to start Aug. 1.

Mired in a corruption scandal and unable to fulfill its obligations to fix the stadium, the Coliseum Commission turned over operations to USC. The university committed to raising $270 million for a major renovation, which is expected to begin after the 2017 football season.

So in the interim, the stadium is making several tweaks to accommodate the Rams.

“Some stuff has just been neglected for years,” Furin says. “The first order of business is to make sure the hot water works and the air conditioning works.”

In the home locker room, USC logos and murals will have to be covered so they don’t show up in the background of Rams TV interviews. To accommodate the NFL press corps, the Coliseum will remove a few rows of seats below the press box and set up benches.

The league also has required that Wi-Fi hotspots be installed on the sidelines so that coaches can make use of their Surface tablets. The connectivity is important for in-game concussion evaluations as well.

The USC and Rams schedules have the teams playing at home on back-to-back days twice this fall. On those dates, the grounds crews will have just a few hours to convert the field from college to pro football, including rechalking hash marks.

In early 2018, the major renovation work will begin. USC is removing the press box and replacing it with a modern structure that will include an expanded concourse and luxury suites. The unsightly video boards on the eastern end of the stadium will be removed, restoring the classical peristyle to its original appearance. New screens will be placed in the northeast and southeast corners of the stadium.

That construction will pause in the fall of 2018 — which, if all goes according to schedule, will be the Rams’ last year at the Coliseum — before resuming in 2019. In 2018, fans will be attending games at, essentially, a construction site. Still, most supporters of the team seem thrilled that the Rams are returning, and are not bothered by the state of the Coliseum.

“Yeah, the seats are broken down, but there’s so much history and tradition,” says Andre Jeanbart, a 41-year-old dentist from West Hills who is a committed Rams fan. “It’s like Fenway Park — it’s a dump. But if you’re a Red Sox fan, it’s an iconic place.”

David Carter, the executive director of the USC Marshall Sports Business Institute, predicts that the real focus will be on the Inglewood stadium, touted as the best ever built in the U.S. Fans, he says, “will tolerate the short-term challenges posed by the Coliseum’s current condition in exchange for getting their NFL fix.”

Architectural renderings of the new stadium make it look like something out of a science-fiction movie, with a sweeping translucent roof capable of displaying ads to planes on their descent into LAX. The plans also call for a 6,000-seat performing arts venue, a hotel, residential buildings, offices, and an artificial lake.

The Rams’ Warwick also senses an eagerness for the new stadium.

“There’s not a football stadium in Southern California that has all those modern amenities,” he says. “People are gonna crave the club seats and suites that we’re gonna create in Inglewood.”