At the age of 65, Bert Shepard can walk 36 holes of golf in less than 51/2 hours. Not bad for a guy with one leg.

But then Shepard is used to surprising people. With the old Washington Senators, he became the only one-legged pitcher in major league history. In 1945-46 the left-hander was getting out hitters such as Yogi Berra, Mickey Vernon, Stan Musial and others. Musial went zero for four against him. When he met Berra again several years later, Shepard was temporarily on crutches. It was explained that he had lost his leg. ''Too bad about your leg,'' Berra told him.

''I had it off then, Yogi,'' Shepard said with a smile.

''You're kidding!'' Berra said.

Shepard pitched in the minor leagues before enlisting in the Army in May 1942. He was his wings and was assigned to fly P-38s out of England. He also managed the Post baseball team.

On May 21, 1944, two weeks before D-Day, Shepard volunteered for a long-range strafing mission. He promised to be back in time for the game that afternoon. Instead, as he made a pass over a German airfield at 20 feet, groundfire came up and caught his right leg. He crashed at 350 mph.

''I woke up two days later in a German hospital and they had amputated my leg,'' he said.

A Canadian prisoner of war made Shepard a crude artificial leg and he immediately took a practice pitch on it.

Repatriated to the United States in a POW exchange, Shepard got a new leg at Walter Reed Hospital. He and amputee-movie star Harold Russell were called in to meet Secretary of War Robert Patterson, who asked Shepard about his plans.

''Well,'' Shepard said he told Patterson, ''if I can't stay in the service and fly combat, I'd like to play baseball.''

Shepard recalled that Patterson looked incredulous. ''You can't do that, can you?''

''If I get a good leg, I'm pretty sure I can,'' said Shepard.

Patterson called Clark Griffin to come out to spring training, which was being held at the University of Maryland because of war-time travel restrictions.

Shepard says he's lucky he didn't lose his left leg instead. ''You need the back leg for balance and since I'm a southpaw, I would drive off my left leg.'' Coming down on the artificial front leg ''doesn't hurt a thing. There's very little handicap as far as throwing.''

On the fourth day with his new leg, Shepard suited up and began pitching batting practice.

''I was thrilled to death,'' he says.

The Senators signed him to their roster, but Shepard didn't get to pitch until July 10 in a war bond exhibition game against the Brooklyn Dodgers in old Griffith Stadium.

The first man up, Leo Durocher, walked, but Shepard got out the next three in order -- Goody Rosen, Augie Galan and Dixie Walker. In the second, he retired Luis Olmo and Frenchy Bordagaray before Eddie Basinki hit a double. Basinski was stranded as Mike Sandlock went out on an easy ground ball. In the third, Shepard got Ernie Rudolph, Eddie Stanky and Rosen, one-two-three.

Shepard ''was befuddling the Dodgers with hs left-handed curve ball,'' Post sports editor Shirley Povich reported in the following morning's paper.

''I was supposed to go three innings, but I shut them out and asked to pitch another inning,'' Shepard remembers. Manager Ossie Bluege assented and Shepard was scored on, though not hit hard.

On Aug. 14, Shepard got into an official American League game. There were 13,000 in the stands watching the Senators take a drubbing from the Boston Red Sox, who had scored 12 runs inthe thrid inning and had the bases loaded in the fourth. Bluege waved for Shepard, who walked to the mound with just a hint of a limp, to face George (Catfish) Metkovich. Shepard struck Metkovich out to end the inning and win a standing ovation.

Shepard pitched five more innings, giving up three hits, a walk and one run. He struck out three. His official ERA for the record book was 1.69. ''Gee, he thought, ''next year I'll be able to make the ball club.''

In March 1946 Shepard joined all the healthy veterans coming back. ''I worked three innings twice, didn't allow a run, one hit, no walks.'' But the Senators cut him. He shrugs philosophically. ''It's hard for a manager to believe his best chance is a guy with a leg off. But I could run good and I could field bunts good.''

At the end of 1946, Shepard joined an American League all-star team touring the West Coast against Bob Feller's all-stars. Shepard pitched and played first base, joining Allie Reynolds and Denny Galehouse on the pitching staff. He got one hit in two at bats against Feller and went one for two against Johnny Sain.

For the next 21/2 years, Shepard was in and out of hospitals for more surgery. Meantime, he had to use crutches and, ''It tightened up the muscles in my shoulder tremendously.'' He couldn't pitch anymore and wouldn't embarrass himself trying.

In 1948, Shepard felt well enough to manage and play first base for the Class B club in Waterbury, Conn. After that, Shepard went to work for IBM as a salesman, then for Hughes Aircraft as a safety engineer and specialist in emloying the handicapped. He was a safety engineer in Saudi Arabia, Abu Dhabi and Venezuela.

He also helps other amputees adjust. When old-time Cubs shortstop Joe Tinker lost his leg in 1947, Griffith asked Shepard to write to him. ''I don't know how to thank you,'' Tinker wrote back.

After Shepard took up golf, he designed and made a natural-motion ankle in 1979, which allows him to walk 36 holes without discomfort. He plays frequently at amputee tournaments and walks every hole.