Jim Brown, Joe Namath, O.J. Simpson, Fred Williamson, Don Meredith, Roosevelt Grier, Merlin Olsen…the roster of ex-football heavies who have tried to parlay stadium success into showbiz stardom grows longer with each season. Then there’s Ed Marinaro.

Ed who? Not too long ago he was just another gridiron has-been—a running back who won fame a decade ago as Cornell’s “Italian stallion,” only to see his career fizzle in the pros. Now, three years after he was cut by the Chicago Bears, last of the four teams he worked for, Marinaro is playing regularly again—this time in NBC’s Emmy-winning Hill Street Blues. Since the new TV season began in October, Marinaro has been featured as patrolman Joe Coffey, the on-and off-duty partner of lady cop Lucy Bates (Betty Thomas). Reckons Ed in a rare understatement: “This has got to be the biggest break of my acting career.”

Get push notifications with news, features and more.

At 31, Marinaro has already had a lot of breaks—not all of them good. Growing up in a second-generation Italian-American family in New Milford, N.J., a working-class New York City suburb, Ed was “arrogant and cocky and unsure of myself,” he admits. At 6′ 2½”, he was also impressive enough as a high school athlete to get scholarship offers from more than 40 colleges. Instead, he persuaded his dad, who runs a sign-painting firm, to help pay for the Ivy League’s Cornell so he could attend its hotel management school. There Ed rewrote the college record books, gaining a then unprecedented 4,715 yards rushing in three seasons. He also set new marks for chutzpah, clamorously protesting when he didn’t win the 1971 Heisman Trophy.

Marinaro’s reputation for self-promotion did not help his pro career. After he made the NFL, Ed tooled around in a flashy purple Porsche and hung out with chums like Broadway Joe Namath. Though he played in two Super Bowls in four years with the Minnesota Vikings, he was never at home there. “Fran Tarkenton didn’t think I was as good as I thought I was,” Ed says candidly. Soon after he went to the New York Jets to run the ball for Namath, he was benched with a foot injury. “When you get hurt in football, people treat you like garbage,” Ed says unhappily. “They wanted to get rid of me, and they did.” He played in just one game for the Seattle Seahawks in 1977, then tried out for the Bears—and was dropped. Though he later got a bid from the New England Patriots, he decided to quit altogether at 27. “I was apathetic,” he recalls. “No way was I going to throw my ass out on the field again.”

Following Namath’s example, Marinaro had been studying drama on the side, and in 1978 he moved to Beverly Hills to give full attention to acting. Then came what Ed calls a year of “groping and searching and having to evaluate my life—the toughest time I’ve ever had.” In 1979 he landed a guest role in a TV series, but the show never aired. He won minor parts in a pilot called Three Eyes, a male Charlie’s Angels that was never sold, and in Laverne & Shirley. In that show, he says unhappily, “I turned into a schlepp. I wore shirts two sizes too small and tight pants.”

Marinaro finally scored last spring, when he introduced himself to Hill Street’s casting director. She had him read for a two-part episode as a cop who was supposed to be killed. But Marinaro proved so appealing in the role that the script was changed to leave him only slightly wounded—and able to sign a contract for $5,000 per episode for 13 weeks on the show. Ed recalls thinking, “Ain’t this a bitch! I no longer have to fight my football image—I’m finally out of that beefcake role.”

Well, maybe. “The first day I met Ed, I was a little uncomfortable because he is so good-looking, big and wonderful,” says co-star Betty Thomas. Ed wants to put his stallion days behind him. He’s long been pursued by women, but claims with pride that “I never woke up feeling cheap.” Waking up exhausted is another thing. “It’s tough when you’re Italian and a football player,” he deadpans. “People assume you’re a superstud in bed.”

Lately he has broken off a two-year relationship—the longest since college—with actress Mimi Rogers, 26. Even when she was with him, though, she knew Marinaro “was a real ladies’ man. He definitely sowed an excess of wild oats. People were shocked and amazed that we were still together after eight months.” Ed himself says he won’t even consider marrying before he turns 40. “But that,” he protests, “doesn’t mean I intend to sleep with a different girl every night.” He says that for the first time, he now sees women as friends and equals. “He’s one of the warmest, most generous and loving men I’ve ever met,” Rogers concurs. “I think he’s gotten far away from his macho image.”

Marinaro insists the image was always a bit phony. Even as a seventh grader, he says, he had to ask friends how to smooch with a girl. “I finally got my first kiss when I was 15.1 had been dating a girl for two months and still hadn’t made a move. We were at a party and she was sitting on my lap when all of a sudden I looked at her and she looked at me and we kissed. Everybody in the room applauded. I was so embarrassed I wanted to die.”