San Francisco 49ers

49ers notes: CB reserves to the rescue; Harbaugh’s puppies bite; Gore proves everyone wrong ... again

A 49ers defense that almost always has five cornerbacks in uniform dressed four for Sunday’s game, then immediately regretted the decision.

One starter, Tramaine Brock, jogged gingerly off the field because of a toe injury in the first quarter. An X-ray showed no fractures. Then the other, Chris Culliver, had to be helped to the sideline after suffering a concussion.

Suddenly, the 49ers’ cornerbacks facing quarterback Tony Romo, wide receiver Dez Bryant and the Cowboys’ passing attack were a rookie, fourth-round draft pick Dontae Johnson, and a journeyman veteran, Perrish Cox, whom the 49ers cut last season.

There was no reason to worry, as it turns out.

Cox intercepted a Romo pass intended for Bryant in the second quarter, one of four 49ers takeaways. Johnson batted away two passes, including one on a critical third-down attempt.

Johnson was one of eight 49ers rookies who suited up and one of four on defense, joining safety Jimmie Ward and linebackers Chris Borland and Aaron Lynch.

“You need to teach puppies how to bite,” coach Jim Harbaugh said.

Cox was let go last season, only to be re-signed before the playoffs when the 49ers needed healthy bodies in the secondary. He admitted his lack of playing time last year caused him to be lazy, and he made sure not to let that happen this year.

Another motivating factor was Cox’s friendship with Bryant, who also played at Oklahoma State.

“He’s like my little brother,” Cox said.

Cox defended Bryant, who was held to four catches for 55 yards, throughout the game, and his interception promises to fill the offseason with bragging rights.

“It’s always nice to get an interception against a great receiver,” Cox said. “But him? I’ve always got something to talk mess to him about now.”

Gore hits 10,000 – It was an innocuous 4-yard run in the third quarter. But when Frank Gore trotted back to the huddle after the play, he had become the 29th player in NFL history to rush for more than 10,000 yards.

Gore finished with 63 yards and has 10,030 for his career, putting him between Ricky Williams and Adrian Peterson on the NFL’s all-time list.

He also is the franchise’s leading rusher and one of only two tailbacks – Pro Football Hall of Famer Joe Perry is the other – to have played 10 or more seasons with the 49ers. Gore, 31, is entering the final year of his contract.

After the game, Gore thanked his offensive linemen and called his milestone “a blessing.” He also noted he’s been fueled by doubters, especially those who didn’t think he could play after two torn ACLs in college. Only one other running back from the 2005 draft, Houston’s Ronnie Brown, remains in the league.

“I wanted to prove everybody wrong,” he said.

Boldin’s big day – Michael Crabtree was eager to play in front of his hometown fans, but it was fellow wide receiver Anquan Boldin who had a big opening day for the second straight season.

Lining up as the slot receiver, Boldin routinely found soft spots in the middle of the Dallas defense, and he finished with a game-high 99 receiving yards. Boldin had 208 yards in last year’s Week 1 win at Green Bay.

Crabtree has been dealing with a calf injury and was questionable. He started the game, but by the fourth quarter, he was watching from the sideline wearing a baseball cap. He had two catches for 25 yards.

Crabtree, who sold popcorn and hot dogs at Cowboys games as a youth, also can expect to be fined for his choice of footwear: blue cleats.

Et cetera – Rookie Bruce Ellington handled kick and punt returns ahead of LaMichael James. Ellington, a fourth-round pick, didn’t get a lot of opportunities, returning one punt for 13 yards and fair-catching the other.

• Brandon Lloyd appeared to be the team’s first option as the No. 3 receiver ahead of Stevie Johnson, although both played. Johnson caught two passes for 33 yards. Two sideline passes to Lloyd were incomplete.

• Practice squad player Lawrence Okoye, who played American-style football for the first time last season, will get an opportunity to play on the defensive and offensive lines this season. He was working on his skills as an offensive tackle during warmups.

• Phil Dawson was wide left on his only field-goal attempt, which came from 37 yards in the fourth quarter. He was 4 for 6 in the exhibition season.

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