SANTA CLARA The only open competition for a starting spot on the 49ers' defense is now closed.
Defensive coordinator Vic Fangio on Tuesday said rookie Eric Reid had won what began as a four-way battle to replace Dashon Goldson at free safety.
"He's had his potholes in there where he's had some mistakes," Fangio said. "Overall, he's just been steady. He's grown in the position, which has allowed his ability to come through more and more. He's tackled well in the games, which is important to us. We lost a really good tackler last year in Goldson. We think Reid will continue to improve as the season goes on."
The announcement means Reid's first official assignment will be matching wits Sept. 8 with Green Bay quarterback Aaron Rodgers, who led the league last year with a 108 passer rating.
Reid's fellow starter at safety thinks the rookie is ready.
Donte Whitner normally calls the plays and organizes the secondary. The seven-year veteran, however, said he occasionally makes Reid do that in practice.
"That's me trying to get him mentally ready," Whitner said. "I want to hear him do it. We need to hear him do it, and it will make us all better."
Reid can be seen as a test case when it comes to the 49ers' plans for maintaining their recent dominance.
With young players like Colin Kaepernick, Aldon Smith and Mike Iupati due for significant contract extensions in coming years, the 49ers know they will have to be selective in which free agents they can afford to keep.
The strategy is to let some valuable veterans go and replace them through the draft. That's what happened this offseason when Goldson, an All-Pro in 2012, signed a big free-agent deal with Tampa Bay in March, and the 49ers countered by moving up 13 spots in the first round to draft Reid in April.
After trading Parys Haralson to New Orleans for a seventh-round pick Monday, the 49ers have 11 picks in the 2014 draft, giving them the ability to target players at specific positions.
The early returns on Reid have been positive.
Like Goldson, he's tall, long-limbed and a hard hitter. And he's shown the smarts and drive to pick up the playbook quickly.
"From high school onto college, he's always been a good student and a student of the game," Whitner said. "You put that together with a guy that's willing to work, and that's how you win a starting free safety spot on arguably the (NFL's) best defense as a rookie. That's hard to do, and he did it."
Reid passed an early test Sunday against Minnesota. On the first play from scrimmage, quarterback Christian Ponder challenged the rookie with a deep pass to wideout Greg Jennings. Reid was the only 49er in coverage, and the ball fell incomplete.
"I like to say I'd have gotten a pick, but you never know," Reid said when asked what would have happened had the pass been on target. "But I was in good position."