The Washington Redskins were all but certain this week they would be without ailing safety LaRon Landry on Sunday, which was about the worst possible news considering the assignment at hand for their secondary. Arizona Cardinals wide receiver Larry Fitzgerald, after all, frequently has made even the most skilled defensive backs look pedestrian, so there was no telling what kind of damage he could inflict with Washington’s top safety out of the lineup.

The Redskins wound up allowing one long touchdown to Fitzgerald, but for the most part, the patchwork secondary held up just fine, even forcing a critical turnover in the final minutes. That’s when backup cornerback Byron Westbrook tackled wide receiver Chansi Stuckey, forcing a fumble, and safety Reed Doughty, starting in place of Landry, recovered to secure the 22-21 victory.

The play underscored the resilience of the Redskins’ defensive backfield in light of Landry’s absence and injuries Sunday to cornerbacks Kevin Barnes and Josh Wilson and free safety DeJon Gomes. The two cornerbacks missed parts of the second half, meaning more work for Westbrook and rookie cornerback Brandyn Thompson.

“These guys got to be ready to go,” Redskins Coach Mike Shanahan said. “We always say you’re one play away from being the starter or two plays away from being the starter. Even though you don’t get a lot of reps, you have to prepare yourself as if you’re the starter.”

Doughty has been doing just that as Landry continued to nurse a sore right hamstring that has kept him out of the first two games. Landry’s injury in last week’s opener against the Giants was part of the reason that Giants wide receiver Hakeem Nicks ran free on deep patterns, and Arizona figured to try to get the ball to the supremely talented Fitzgerald.

Fitzergald had been limited to six receptions for 60 yards going into the fourth quarter, but with 11 minutes 18 seconds left, he beat veteran cornerback DeAngelo Hall one-on-one down the right sideline on a double move. Quarterback Kevin Kolb released the ball a split second before he was hit hard, and the ball settled into Fitzgerald’s arms for a 73-yard touchdown and a 21-13 lead.

“I felt like I lost it,” Hall said of his matchup with Fitzgerald. “It was nice to come out with the win, but like I was telling Coach [Shanahan] — he said, ‘I probably shouldn’t have put you in that [position] — I said, ‘You know what? I’ve got to win that.’ I’ve got to be smarter. I can’t go out and win 99 out of 100. I’ve got to win 100 out of 100. That’s what I expect of myself.”

Hall’s secondary mates came to the rescue in dramatic fashion at that. After the Redskins scored the next nine points for a 22-21 advantage, Arizona took possession with 1:45 remaining, and the most sensible strategy seemed getting the ball into Fitzgerald’s hands just about any way possible. On first down, Kolb instead threw to Stuckey, the Cardinals’ No. 4 wide receiver. Almost immediately after the catch, Westbrook swooped in to jar the ball free.

Doughty fell on it at the Cardinals 32, but officials initially ruled Stuckey was down by contact. After some tense moments on both sidelines, a booth review reversed the call, and Washington had escaped, despite allowing 133 yards and a touchdown to Fitzgerald.

Among the top 10 leaders in tackles on the Redskins, six were defensive backs, including two tackles and three assists from Hall and three tackles and an assist each by Westbrook and starting free safety Oshiomogho Atogwe. Wilson had two tackles, and Thompson contributed two and Barnes notched a tackle and an assist.

“Our coach always focuses on turnovers,” said Westbrook, who played high school football at DeMatha. “The more turnovers we have, the more chance we have of winning. When the guy caught the ball, he didn’t see me behind him, so I just went and took a swipe, and the ball came out. Game over.”