Midway through the third quarter last night in Capital Centre, Julius Erving took a long pass and then took flight toward the basket at the end of a fast break. When the regal Doctor is preparing for another stratospheric stuff, most mortals back away in awe.

Rick Mahorn suddenly invaded Erving's space. As the best acrobat in basketball readied the ball to be dunked, or kissed gently off the glass, the Bullet center flicked it off his hands. Rick Unknown blocked the Doctor. It's a way for a man to get noticed.

"He belongs, all right," Caldwell Jones was saying of Mahorn after the semicrippled Philadelphia 76ers slipped past the WashingtonWorkaholics in the final two minutes, 95-92. "So does the other big guy (Jeff Ruland). Haven't found a weakness yet, 'cept they might be slow picking up a bill."

The Big Bullet Babes, Mahorn and Ruland, were as nice as you'd want against the Sixers. Have been all year. As Billy Cunningham said: "Bob Ferry and Gene Shue have to be ecstatic about 'em. Ruland looks like he's been in the league for years. All Mahorn can do is get better."

They are Woolworth-rated players holding their own against the Tiffany's of the NBA. They have helped make the Bullets mediocre, which is more than most non-Bullets thought possible before the season, and just might be the foundation of a contender some year.

Both were drafted on the second round, Mahorn by the Bullets and Ruland by Golden State in '80. Mostly, anyone chosen after the middle of the first round is lucky to make a team, let alone start and make a major contribution his second season.

This was the Bullet lineup that gave the playoff-tested Sixers all they could handle in the final eight minutes: rookie Frank Johnson and rookie Whatshisname Witts at guards, rookie Ruland, rookie regular Mahorn and Greg Ballard up front.

The Sixers had their real players on the court most of that stretch: The Doctor, Caldwell Jones, Maurice Cheeks, Lionel Hollins, the crowd that seems to feel it must apologize each year to Philadelphia for not quite winning an NBA title.

In truth, Philly was at less than full strength the entire game. Bobby Jones and Andrew Toney did not play at all. And Darryl Dawkins spent most of the game as a spectator, in foul trouble, seeming in his seventh year no more advanced than Mahorn in his second.

You have anybody healthy? Cunningham was asked.

He paused, head cocked in thought, then said:

"Guess the only healthy one is Franklin." That would be rookie Franklin Edwards, who hardly ever plays.

Still, the Sixers were playing hard. Losers in three of their last four games, they tried from the first shot to the last. Erving played defense almost as well, if hardly as spectacularly, as offense. Twice he tried to flick the ball from a Bullet 20 feet from the basket; he blocked three shots and had four steals.

But the inspired Sixers could not shake the Bullet Babes. Ruland ev en matched Mahorn in Legend Stuffing, slapping the ball from Erving with 4:04 left and the Sixers ahead by two.

Washington had a wonderful chance to win, and very well might have if the best anonymous player in the NBA, Caldwell Jones, had not been at his rejecting best. No sooner would Mahorn or Ruland get the ball low, in position for a field goal, foul or both, than C.J. would gently slap it away.

In all, this was a fine night for devotees of the art of shot blocking. And few are more adept than the 7-foot C.J.

He had five in all, and all came in the fourth quarter. He blocked Mahorn and Ruland twice each and Spencer Haywood, a nonfactor in 25 of his 26 minutes, once.

"Lots of times a guy gets the ball down low and it's a mistake on my part," said C.J., the eternal ice pack planted atop his right knee almost immediately after the three-point victory. "But these guys were setting good picks to get open.

"I was beat, no doubt. Blocking was my only alternative, and I was lucky to get 'em."

Enthusiastic as many Bullet watchers are becoming over this team many thought might not win a quarter of its 82 games, realists suspect last night was a telling game. Although just four games under.500, they probably are just good enough to lose heroically to the NBA's elite.

"They'll get over it," Cunningham said. "I think so."

Watching Jeff, Rick and Frankie grow won't be all that bad this year. They might even grow into a playoff team sooner than anyone imagined. The Sixers were nodding their heads in respect, grateful that their experience proved decisive at the end.

"I noticed the first time in Philly that Ruland likes to give you a lotta ball fakes down low," C.J. said.

Any other ways the Bullet Babes telegraph their scoring punches?

"Nope."

Or none that C.J. wanted to reveal.

"I'd love to have them on my team," he said. "Any day."

The Sixers' trainer was stooping to examine CJ's knee, but the center looked up and offered one last line.

"Ruland's weakness might be three-point shots," he said, smiling, pleased at this bit of absurdity.

Ah, C.J., Ruland hit a three-pointer Sunday against the Knicks in New York.

"Oh."