During Saturday's practice, Tramaine Brock showed why the 49ers felt comfortable moving on from long-time starting cornerbacks Carlos Rogers and Tarell Brown in the offseason.
Brock, who has been lining up at left cornerback, picked off one pass during the afternoon practice and in quick succession broke up two others. It was an early indication that his team-leading five interceptions a year ago plus the tipped pass that linebacker NaVorro Bowman snagged against Atlanta were not an aberration.
Jim Harbaugh said that both Brock and the starter on the other side, Chris Culliver, who appears fully recovered from last years ACL injury, are playing at a different level from the other cornerbacks on the team. The stance was echoed by general manager Trent Baalke.
We feel good about the group, we really do, he said. ... Brock and Culliver are two very competitive, very gifted athletes, and you see that every day out there.
Still, cornerback remains the 49ers' biggest question mark from a position standpoint going into the season. Brock and Culliver, after all, were the team's top backups in recent years and provided excellent depth. The players competing behind them this year are unproven.
One of them, Chris Cook, appears to be the frontrunner for the role of No. 3 cornerback. Cook, a former second-round pick who struggled in Minnesota, has more experience than any other cornerback on the team, including Brock and Culliver. At 6-2, 212, he not only is the 49ers' biggest cornerback, he's bigger than all of the safeties as well.
Cook's forte, naturally, is press coverage, something he says he's been able to hone in practice against physical receivers like Anquan Boldin, Michael Crabtree and Stevie Johnson. Perhaps his biggest challenge is veteran Brandon Lloyd, who is as crafty and as slippery as any receiver in the league. Lloyd doesn't have blazing speed, but he was able to get past the defense last week for an easy, 60-yard reception, the longest so far of training camp.
His routes are so good, man, Cook said of Lloyd. Everything he runs, it just looks like he's about to take off and go straight down the field. You can't really get good reads on his routes. It makes you stay honest and play your technique true.
The others competing for backup spots are veteran Perrish Cox, second-year player Darryl Morris and draft picks Dontae Johnson and Kenneth Acker. The 49ers also drafted a safety, Jimmie Ward, in the first round. However, the wasp-waisted Ward in many ways resembles a cornerback, and his first role will come as the team's nickel cornerback.
Said Baalke: Jimmie Ward -- theres a guy that hasnt had any OTAs, hasnt been in cleats since the end of the season. And he steps in and seems to get his hands on balls every day.
Read Matt Barrows blogs and archives at www.sacbee.com/sf49ers.