In the course of events, perhaps it should have been expected. Yesterday, as Washington Redskins Coach Joe Gibbs tried to explain his team's 35-17 loss to Miami in Sunday's sullen start of a new season, a lightning storm hit and all light in Redskin Park vanished.

"It's been a tough couple days," Gibbs said with a shrug and a meager 'what next?' smile.

The Redskins' woe mounted even higher yesterday when it was learned that reserve tight end Mike Williams suffered a hairline fracture in his neck during a special teams' play Sunday and will be out six to eight weeks.

Williams likely will be placed on injured reserve, leaving the team with only one reserve tight end, rookie Anthony Jones. While Gibbs said he would decide last night whether to fill that spot with another tight end (Clint Didier is on injured reserve and can't return until the fifth week), General Manager Bobby Beathard was on the phone in his office, he said, looking for any available tight ends for immediate help.

Most of the explanations, though, were left for the defensive coach, Richie Petitbon. His unit utterly failed in pass defense Sunday at RFK Stadium, yielding five touchdown passes to Dan Marino and failing to sack him even once.

Petitbon said he remains confident in the secondary and plans no changes in players there this week.

"I really don't think you can fault the pass rush," Petitbon said, "when a team throws that quick, with three-, four- and five-step drops."

The defensive line coach, LaVern (Torgy) Torgeson, said that tackle Darryl Grant will be able to play Monday night and added, "Maybe Miami saw that we sacked New Orleans seven times last week (in a preseason game) and (consequently) they threw quicker than usual to negate our pass rush."

Twice Sunday the Redskins' pass defense gave up touchdown passes due to coverage mixups. The most crucial was a 74-yard play from Marino to wide receiver Mark Duper that gave the Dolphins a 14-10 lead with two minutes left in the half. This ruined the Redskins' ball-control momentum, about which Gibbs said, "It was all totally in our control until that (74-yard) play."

Petitbon said he was not angry at cornerback Anthony Washington, who did not follow the design of the zone defense by going with Duper to midfield, where Duper caught the ball. Instead, Washington stayed at the line of scrimmage. "Anthony should have rolled (with Duper), but he didn't play it that bad," Petitbon said.

Rather, Petitbon was more angry at cornerback Darrell Green, who failed to tackle Duper near midfield, in his deep portion of the zone. "A missed tackle cost us 50 yards and a touchdown," Petitbon said.

However, Petitbon admitted, some of the fault may have been his own. He said the Redskins hadn't practiced that particular zone defense since training camp and that it was made as an adjustment to counter the Dolphins' offensive set that stationed receivers Duper and Mark Clayton on one side and wide receiver Jim Jensen (two touchdown catches) in the slot on the other side.

"Our guys (in the secondary) are still fairly young. We probably should have waited until halftime" to discuss the adjusted zone coverage, Petitbon said.

There also was confusion in the secondary on Marino's final scoring pass, a four-yarder to Jensen late in the third quarter that skied the lead to 35-10 and crashed-landed Redskins hopes.

Nickel back Brian Carpenter was confused on the play and failed to cover Jensen, who was lined up on the right. By the time free safety Mark Murphy tried to help out, Jensen was spiking the ball in a touchdown celebration.

"When Brian couldn't find his man in nickel (coverage), that's an individual responsibility," said Petitbon. "It's strange because he had been covering (Jensen) all day in those situations. It's hard to explain. It makes you wonder what you do all week in practice."

It also makes you wonder what will happen Monday night in Candlestick Park, when the Redskins face Joe Montana, San Francisco's resourceful quarterback. In last year's conference title game against the Redskins, Montana threw three touchdown passes in an eight-minute span of the fourth quarter, tying the score at 21. The Redskins revived to win, 24-21.

Petitbon said no personnel changes will be made in the secondary this week. He said he did not think the Redskins tipped off their blitzes against Miami, as some suggested, or that cornerback Washington played as badly as it appeared.

"I don't think you can become too down on the secondary for one game," Petitbon said, citing the fact that Marino was "a quarterback with a very hot hand."

He said strong safety Tony Peters, who was matched against Jensen, "wasn't as sharp as we'd like him to be. It wasn't one of Tony's better games." He also said he expects gradual improvement from Peters, who missed all of last season.

Gibbs was sure to note that the Redskins' offense was not without blame, either. Running back Joe Washington fumbled and quarterback Joe Theismann threw an interception, leading to two of Marino's three third-quarter touchdown passes. Last year, the Redskins led the league with a plus-43 turnover ration. Sunday, they rated a minus-3.

"The offense did not go by the principles we go by," Gibbs said of the turnovers. "In the Super Bowl (a 38-9 loss to the Raiders), we didn't stop their run and they stopped our rushing game, and that's why we lost. That's logical to me . . . This game was different. It was like the Packers' game last year (a 48-47 loss). We gave up big plays and lost."

Gibbs was more critical of the Redskins' pass rush than Petitbon: "(Miami) won't beat you with three-step drops. With a three-step drop, the farthest you'll throw is seven yards. They weren't beating us with seven-yard plays. Yeah, they got a few of those in there.

"A lot of them, though, were five-step drops (by Marino), going with 12- 13-yard patterns (by receivers). Some were posts (patterns), some came against our blitzes, and they did a good job with (quarterback) protection.

"I want more pressure than that. Part of the reason (for no sacks) was that (Marino) got the ball off quick . . . (But) that's no excuse."

Gibbs said the team will not look for players from other teams to help the secondary. "I still feel like our solutions are right here," he said.

Now, the Redskins' defense has been pushed to the limits in three consecutive games: from San Francisco's quick-strike pass attack in the NFC conference game, to the Raiders' Marcus Allen-run attack in the Super Bowl to Marino's bombs-away job Sunday.

Asked if teams have learned the Redskins' truest defensive weakness, Gibbs said, "I don't think that's the case because each one of those three games was different in what was done to us. I don't think there was a central theme or a central key that says, 'Hey, this is what they are doing.'

"I think that's what we'll be seeing, if we can match up with real good teams. I think that last year, we were able to do that, without throwing the Super Bowl in there. I think each year is new . . . Whether we're able to do that this year or not, that's what we'll find out."