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SANTA CLARA – The 49ers made a major tactical switch last week that paid dividends in their 16-10 victory over the New York Giants.
With rookie defensive back Jimmie Ward out for the season with a fractured foot, defensive coordinator Vic Fangio and defensive backs coach Ed Donatell unexpectedly moved rookie Dontae Johnson to replace him in the role of nickel back.
Ordinarily, starting left cornerback Perrish Cox would have moved inside to cover the slot receiver on passing downs, leaving Johnson to take Cox’s spot on the outside.
But the 49ers liked the matchup of Cox remaining at cornerback to cover rookie Odell Beckham, while placing the 6-foot-2 Johnson in the slot to match up against Preston Parker (6-foot).
“We just thought that gave us the best chance and the best combination of guys, even though Cox could’ve gone inside and Dontae could’ve gone outside,” Fangio said. “(We) just felt that that was the best combination.”
After the Giants gained a first and goal at the 49ers’ 4-yard line late in the gmae, Eli Manning tested Cox against Beckham on a fade route. Incomplete.
On fourth down, Manning went after Johnson in the slot. Johnson got a hand in front of Parker, deflecting the ball into the hands of linebacker Chris Borland for an interception.
“I feel coaching staff feels comfortable with my knowledge of the game and understanding of playing nickel,” Johnson said. “They feel like I can step in and play within the defensive scheme and make plays when they’re presented to myself.”
It was the second time Johnson had late-game heroics. His interception return for a touchdown sealed the 49ers' 31-17 victory over the St. Louis Rams on Oct. 13.
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But just because Johnson played the slot role a week ago does not mean he will be back in the same role against Washington on Sunday at Levi’s Stadium. Washington has two smaller, quicker slot receivers: Andre Roberts and DeSean Jackson.
“Of course, little guys have that advantage on me,” Johnson said. “But at the end of the day, I play corner. You have to have that quick-twitch, and I feel like I have it.”
Cornerback Tramaine Brock remains out with a hamstring string, so Johnson will see a lot of action on Sunday. Fangio would not say where Johnson will line up when he enters as part of the 49ers’ nickel defense.
“We’ll analyze that every week and feel like where’s the best place for him to play, factoring in where’s the best place for Cox to play, too,” Fangio said. “It’s interchangeable.”