The Washington Bullets' struggle to reach the 500 mark hit an unexpected road-block tonight: the Detroit Pistons.

The team with the league's worst record (now 12-35) did the Bullets in for the second time this season when guard John Long tapped in a missed Bob McAdoo shot with 20 seconds left to key a 110-107 Detroit victory.

Long's tip-in, giving him 24 points and eight in the last three minutes, erased a 107-106 Bullet edge. The Bullets called time out, then cleared the baseline for Elvin Hayes.

Hayes' 10-foot jumper over Long went off the rim and McAdoo, the game's high scorer with 29 points, grabbed his 15th rebound. He was immediately fouled by Greg Ballard and made both shots for a three-point lead with four seconds to play.

The Bullets called another timeout and got the ball to Ballard but his falling-down shot for three points from beyond the top of the key hit the back rim and bounced away at the buzzer.

Thus, the Bullets, who have not been at .500 since Nov. 24, dropped to 20-23 heading for a game in Houston on Friday (WDCA-TV-20, 9 p.m.)

"You just can't afford to lose to the worst team in the league," said Hayes, whose output was 17 points. "We shouldn't be even with this team for four quarters like that. We should just win these games. It's time we start playing for pride around here."

About his final miss, Hayes said: "The play is over, the game is over, it doesn't matter what you think now." But he added: "He (Long) came under me, he hit me with an elbow as I went up. But the ref didn't call it, that's just the way it goes."

As Coach Dick Motta said, this game typified a frustrating season for Washington. The Bullets never led by more than five points and that was at 11-6. Each time the Pistons built a lead -- as many as 12 points -- the Bullets came back. But they could never gain control.

"Typical," Motta said. "We've only been blown out five or six times. We had our opportunities to win it in the fourth quarter and we missed our shots. We also missed three foul shots the last quarter. When you're playing like we've been playing, you can't afford that."

"It isn't any one thing," said Wes Unseld, who had 15 rebounds. "It's all the little things. A different thing every night."

Tonight it was shooting -- 42 percent for the game, 37 percent the second half. Hayes (six of 18); Unseld (two of seven); Larry Wright (three of 11) and Bob Dandridge (eight of 18) were more than Ballard's nine of 15 could overcome.

With McAdoo playing a strong all-around game in the absence of starting center Bob Lanier, who is out with a broken hand, the Pistons played a solid game from start to finish.

They hit 10 of their first 15 shots for an early nine-point lead and never trailed by more than two points the rest of the night.

The Bullets trailed by as many as 10 in the third quarter but quickly got even at 84-84 two minutes in to the fourth quarter.

From that point -- with Mitch Kupchak going six minutes at center for Unseld and Dandridge in for Hayes (five fouls) -- the lead seesawed. Long tied it for the final time 100, with 2:34 left.

The Bullets missed open jumpers their next two possesions and Long made jumpers each time for a 104-100 Detroit lead. Hayes' three point play with 1:35 left made it 104-103. Jim Cleamons and Terry Tyler traded baskets before Long was called for charging with 55 seconds left.

The Bullets called time. Hayes missed a jumper but Ballard's follow banked in and it was 107-106, Washington, with 38 seconds left.

The Pistons set McAdoo up but he was off the mark.

"I was on the right side and everybody was boxed out when Mac went up," said Long. "(Kevin) Grevey took his eyes off me and was looking at the shooter. I just got the position and went up and tapped it."

The loss was the Bullets' second in a row and the third time this season the Pistons have won two in a row.

"It's got to get better," Hayes said. "It certainly can't get any worse."