Joe Gibbs called it one of the hardest decisions he's ever had to make as a head coach.

And when the call came from the Redskins coach to the backup quarterback to begin warming up on the sidelines, Doug Williams admitted, "I had to look around and see if he was talking to somebody else. My heart nearly jumped out of my chest."

Still, as the crowd of 53,593 roared its approval, Williams controlled his emotions and threw two touchdown passes before halftime, leading the Redskins to a 20-13 victory over the Detroit Lions and enveloping this town in yet another classic quarterback controversy.

Schroeder vs. Williams might not quite have the ring of Sonny vs. Billy or even Kilmer vs. Theismann, but for now, it will have to do, particularly after Gibbs had insisted all week he was "always reluctant to change the quarterback."

Immediately after the game, Gibbs named Williams his starter for the team's next game, a week from tonight against the Los Angeles Rams at RFK. Gibbs said he wants Schroeder to work on his throws under the tutelage of quarterbacks coach Jerry Rhome, and he placed no timetable on his return to the starting lineup. This was the first time in his seven seasons in Washington that Gibbs benched a quarterback with a game still undecided.

Williams was by no means the only hero yesterday. Four Redskins interceptions -- cornerback Barry Wilburn's sixth of the season and cornerback Darrell Green's third of the game -- helped assure Washington's victory, as did a raucous RFK crowd that made life miserable for Detroit's second-year quarterback Chuck Long.

Schroeder was miserable, too. After the game, he declined to comment on the switch.

But Williams' performance when he first entered the game made the difference, many Redskins said. Some also said they, too, were surprised by Gibbs' decision to go with the backup.

"I was flabbergasted," tackle Mark May said of the switch. "Through all my years with Joe {Theismann}, he never came out of a game, even when he was going bad. And I tell you, there were times I thought he would come out. But I'm happy for Doug, and I feel for Jay. What else can I say?"

"Williams gave our team a big lift," General Manager Bobby Beathard said. "We needed a lift at that particular time. Without that, we wouldn't have won this game."

Williams, 32, who started for five seasons with the Tampa Bay Buccaneers, completed 11 of 18 passes yesterday for 161 yards and touchdowns of 16 yards to running back Kelvin Bryant and 42 yards to wide receiver Gary Clark.

Williams started a game at Atlanta earlier this season when Schroeder sprained his right shoulder. Schroeder is healthy now.

"I may have rushed Jay back into playing after the strike," Gibbs said. "He's inaccurate right now. I didn't make it based on a sack. It's not based on two or three throws. It was a hard decision for me to make. I know Jay's upset about it, mad about it. But I know this is something he can come through."

Gibbs showed almost no reluctance to change the quarterback yesterday. In the first 1 1/2 quarters, Schroeder overthrew open receivers twice, was nearly intercepted twice and fumbled on what turned out to be his final play of the day.

Schroeder finished with five completions in 10 attempts for 33 yards, no touchdowns and no interceptions. Ironically, his 50 percent completion percentage was better than his season average of 40 percent.

Schroeder, who had played poorly in two of his three games before this one, huddled under a burgundy cape on the Washington bench between offensive series as Gibbs summoned Williams. This was a surprise to almost everyone on the sideline, players said later. Including Williams.

After sending Williams to warm up, Gibbs walked over to Schroeder.

"I made a decision to go the other way," Gibbs said. "I know you don't like it, but I'm going to do it."

How did Schroeder respond? "He didn't say anything," Gibbs said.

He also didn't say anything to reporters in the locker room. He looked out from his locker and said, "It's gonna be a while, so you might as well forget it."

Minutes later, Schroeder left.