It is the bottom of the ninth and the Christians are being mauled 7-0 by an irreverent team of paving contractors. The boys in the dugout, 17- to 19-year-old hardballers, look chastened.

Their coach, a stocky, rock-jawed man with a cross on his baseball cap and a radio to his ear is wearing a look of only slightly distracted satisfaction.

"I'm listening to Jesus," says Edsel B. (for "Born Again") Martz, pointing to the night sky above his sandlot. "Baseball is no longer my main object."

It sounds like blasphemy to many of the old timers on Washington's now anemic sandlot scene. Some of them have known the 55-year-old ex-Marine drill sergeant since his catching days at Eastern High School where he once punched an opposing pitcher for striking him out.

In a chorus they will tell you that no one has ever been as hardnosed as Martz in the pursuit of victory. Until last year his team played or practiced 7 days a week, 365 days a year.

"It's hard to believe that Martz has found anything more important than baseball," says one graybeard who coached against him. "Compared to Martz, Vince Lombardi was a damn sissy."

Martz is still fond enough of the grand old game to put up a few thousand dollars from his insurance each year to sponsor and coach a team in the Clark Griffith League. But now reaching home on a single from second is slightly less crucial than eternal salvation. And instead of advertising Martz Insurance, his team's jerseys now read "Sponsored By Jesus."

"The Word has to go out," says Martz, who cashed in a $9,000 life insurance policy this year to carry on his baseball mission. "That's the only reason I'm hanging in here."

Martz does not demand that his players be born-again or even Christians. In the five years since he was "saved," by a television evangelist (Martz was only half listening as he typed out an insurance policy) he has coached Catholics, Jews, Protestants and agnostics. Some of his Jewish players, he says, have found the team jerseys a tight fit.

"I don't pour my religion down their throats," says Martz who has authored two pamphlets of sports tips for "teen-age boys," as well as a Christian reader for "people who would rather turn than burn."

What he does pour, splash and deluge his players with are such baseball commandments as: "Don't chicken out on a hard grounder . . . A bruise on your body will disappear. One yellow stain on your heart will never disappear," and "Like when the monkey kissed the porcupine, learn to take the good with the bad."

The players bow to Martz's authority, though not always with perfect obeisance. A former players, who was thrown off the team last year because of his "bad attitude" says players often made secret fun of Martz and his faith.

"A lot of players get turned off by the religion thing," says Mark Matulia, a senior at Seneca Valley High School in Montgomery County and a born-again Christian. "But most of the players appreciate what he's trying to do for us."

While Martz's main goal may be saving souls, his more immediate concern is getting his players polished enough to win college scholarships or even professional contracts.

In the last seven years, more than 25 of the ballplayers who have competed in the Griffith League have earned paying jobs with minor league teams. Another 80 players have won college scholarships.

The 36-year-old league, named for the former owner of the original Washington Senators, is a way station for teen-agers with major-league ambitions. Players from this area, and all over the country, spend their summers at George Mason University's field in Fairfax City, sweating out the fundamentals six days a week, hoping to be transformed from sandlot suspects to big-league prospects.

"I'd be willing to trade my life now for college or the minor leagues or anything else," says David Boswell, a 1979 graduate of McLean High School who worked last year for minimum wages assembling fruit baskets. That year in the "real world" he says has given him a craving for baseball success that is worth sacrificing a bit of summer fun.

"Pro scouts aren't looking for a kid who doesn't want to play both games of a doubleheader," explains Mike Vlahos, the 60-year-old president of the league. "If a kid wants to go away over the 4th of July weekend, I tell him keep going."

Vlahos is the organizational life of the Griffith League, and he is the first to admit that both he and his league have been sick of late. The league almost folded earlier this year when Vlahos was ill. It finally opened with only four teams, half the number that it once fielded.

"It's hard to find sponsors," says Vlahos, sitting with a loyal corps of a dozen fans watching the Christians struggle against Mack's, this summer's league powerhouse.

"This ball club brings in trained horses, already polished," said Martz, nodding in the direction of Mack's pitcher Ty Hubbard, a junior college star from Spartansburg, S.C., and one of six starters on Mack's team from states outside the metropolitan area. "I'm not knocking what they do," said Martz. "If I had the money I'd do that kind of recruting too."

Martz has his own contingent of outside talent to complement his local players. He advertises for "pro prospects only" in national sport papers such as The Sporting News. In return for their baseball service, he helps find them jobs and places to live.

Too often, complains Martz, for all his money and effort, he gets only half hearted efforts from kids who just don't seem to have the grit they used to.

"This new bunch of kids we're getting don't have discipline. They never suggered," said Martz, who sometimes tells his players to give themselves a rap on the shin with a bat to get in the right frame of mind.

Last week, against Mack's, Martz's Christians were sorely in need of some additional help. Except for a three-hit rally that produced two runs in the ninth inning, the spirit was not with them at the plate. They lost 7 to 2.

"If you can't handle the heat, you ain't going nowhere," said Martz in a post-game dressing down that seemed a bit muted without baseball's normally professional profanity.

"I don't curse anymore," said Martz. "Being a Christian is tough."