With the Redskins ahead by 24 points midway through the fourth period and RFK Stadium less than half full, Coach Joe Gibbs yesterday still was running Joe Washington around end and sending Art Monk deep down the middle on fly patterns.

"I just didn't think we had it put away," Gibbs said after his team had defeated the Colts, 38-14, Baltimore's 14th straight loss this season. "We lost a game once (in college) when we pulled the starters too early. I didn't think we had things wrapped up until the last few minutes."

Gibbs probably has seen too many erratic bounces and fluke plays in his first season as head coach in the pros to relax anyway. But this game was over by the half, when the Redskins held a 28-7 lead over the team with the worst record in the National Football League.

Washington presented itself a 7-8 record, assuring progress from last season's 6-10 mark. The Redskins have won seven of their last 10 games and five straight at home. And going into next Sunday's finale at Los Angeles, they are alive, mathematically, for the second NFC wild-card spot -- as long as Atlanta loses tonight to the Rams (see story, Page B4).

The Colts' season only got worse. Their losing streak, after an opening game victory, tied the league season record for consecutive defeats. And now they hold NFL season marks for most points surrendered (512), most first downs allowed (386) and most yards given up (6,443).

"This was a no-win situation for us, really," said Redskin safety Tony Peters. "We didn't want to be the ones who lost first to the Colts. Last night, I was lying in bed thinking of other things and I said, 'Get your mind on the Colts or you'll be sorry.' "

The Redskins kept their minds on the Colts long enough to break away from a 7-7 first-quarter tie and score on five straight possessions. Baltimore's second touchdown didn't come until Washington had built a 35-7 lead.

Redskin statistics against the Colt defense were impressive: 486 total yards (second highest of the season), 27 first downs, 339 passing yards.

Joe Theismann completed 23 of 36 passes for those 339 yards and two touchdowns. He ran eight yards on a quarterback draw for another touchdown. His year's totals (474 passes, 279 completions, 3,321 yards) now rank as the second best by a Redskin quarterback, topped only by Sonny Jurgensen.

Monk, struggling the last few weeks, caught seven passes for 148 yards, a personal high for him, and one touchdown. Joe Washington, playing against his former teammates, ran for 73 yards and had five receptions for 61 more yards. John Riggins, despite a bad cold, rushed for 50 yards on only seven attempts and scored twice.

"We wanted to be aggressive," Gibbs said. "We figured we had to make things happen, we didn't want to sit back and wait. So we came out after them."

The Colts helped by blitzing on almost every early down, especially in the second half. Once the Redskins saw their receivers getting mainly single coverage, Gibbs reduced his running calls and ordered more deep passes than in any other game this season.

As Monk said, it was the kind of game receivers love. "We like to make big catches and create some excitement. Going in, we thought we could do anything we wanted, as long as we played well, and we did."

If Washington receivers had not dropped a couple of those long attempts, the final score would have been even more lopsided. But the Colts also will remember one muff as being particularly damaging.

That came with the Redskins ahead, 21-7, late in the second period. Theismann's pass down the left sideline from the Baltimore eight went into the hands of cornerback Larry Braziel, who had open field ahead. Braziel juggled the ball for five steps, then dropped it.

"If I hadn't had gloves on, I would have caught it," Braziel said.

Instead, Washington kept possession. Two plays later, on third down with the first-half clock nearing expiration, Theismann waved off a play call from Gibbs and took the advice of center Jeff Bostic, who wondered if a quarterback draw wouldn't be effective.

"Everyone from Baltimore was trying to pinch in from the sides and the line thought they could open a hole up the middle for me," Theismann said. "But when the play started, the Colts ran a stunt and one guy came right in on me. I had to sidestep him, and get away from another, before I could get into the end zone."

Mark Moseley's extra point gave the Redskins a 21-point lead, the type of hurdle the Colts have not been able to clear all season.

Until then, Baltimore's offense had been able to pick up yardage. The Colts had 191 total yards in the first half, including 148 passing by Bert Jones, who played despite a sore shoulder.

"That's what worried me," Gibbs said, explaining why he didn't replace Theismann with Tom Flick until 3:10 remained in the game. "The Colts can score so fast and their offense is so good. I kept seeing receivers fly by me all day."

The Redskins scored on the game's opening possession when Theismann found Virgil Seay open down the right sideline for a 38-yard touchdown completion. No Colt was within 10 yards of Seay; Baltimore free safety Reggie Pinkney had decided to double-cover Monk across the middle.

A 10-yard pass from Jones to Raymond Butler with 1:45 left in the quarter tied the game, but the Redskins regained the lead with a 78-yard drive that ended when Riggins scored from eight yards out.

"John was pretty sick," Gibbs said, "and we picked our spots with him. But he sure ran well. We just didn't want to push him too much."

Another Riggins scoring run, this one a tackle-breaking thrust of 14 yards, increased the advantage to 21-7. Then free safety Mark Murphy intercepted a tipped pass, the eighth straight game in which he accounted for a turnover, to set up the fourth Redskin touchdown of the half.

A fine leaping catch by Monk and a 38-yard Moseley field goal around another Jones touchdown pass finished the scoring.

"The beauty of our offense is that we don't have to force long passes," Gibbs said. "They are there every week, it just depends on how they play defensively. Today, we took advantage of the chance to throw long.

"I told (Baltimore Coach) Mike McCormack that I wanted to run the ball more in the second half, but they kept blitzing so much we had to throw."

Said Theismann: "Joe Gibbs must be the most relieved man in Washington tonight. He's been so nervous about this game, we almost had to calm him down. Guess we aren't used to being favored over many teams, that's all."

Mike Nelms set a Redskin record for combined return yardage in a season, 1,502, by shaking the Colts for 29 yards in punt runbacks and 41 with kickoffs . . . Receiver Alvin Garrett fractured his right arm, the major injury reported by the Redskins. Others hurt included Brad Dusek (bruised thigh), Joe Jacoby (bruised knee), Otis Wonsley (sprained knee) and Peters (bruised ribs) . . . There were 8,339 no-shows, the most empty seats this season at RFK.