SANTA CLARA One week after watching Michael Crabtree go down with a torn Achilles' tendon, 49ers coaches must have been pleased by what they saw from another veteran wide receiver during Tuesday's workouts.
There was Anquan Boldin catching a pass down the seam over inside linebacker Patrick Willis. There was Boldin darting to the outside for a sideline reception. There he was splitting two defenders and snagging a ball in the end zone.
One thing is clear for the 49ers as they begin preparing for the 2013 season: Boldin will start at one receiver spot, and he showed it might not take long for him to take over Crabtree's role as Colin Kaepernick's favorite target.
"You got a good look at what he's been doing," coach Jim Harbaugh said. "Really picked up the system fast making plays, big catches in tight areas. You saw what we've been seeing for a couple of weeks."
What's murky, and likely to remain so until training camp in July, is the identity of the other starting wideout.
Harbaugh said Boldin will start at flanker, but the split end position is a competition among a group of promising but inexperienced players, including last year's first-round pick, A.J. Jenkins, rookie Quinton Patton and Ricardo Lockette, who spent most of last season on the 49ers' practice squad.
Boldin said it was a smart approach because it already has sparked intense competition. Jenkins and Chad Hall were the wideouts with Boldin when the first team ran a two-minute drill at the end of practice. But all of the receivers were rotated through the lineup during the session, and no one seemed to get a larger share of the repetitions opposite Boldin.
"I see a bunch of guys that want to make their mark, that want to put their names out there," said Boldin, who is entering his 11th season. "Coach said it's an open competition on the other side, which I think is one of the better things he could have done. It really forces guys to come out and work hard every day."
Boldin showed the same ability to snatch passes in tight spaces that he did in the Super Bowl against the 49ers. He led the Ravens with six catches for 104 yards, including a touchdown in the first quarter and a critical third-and-one conversion late in the game.
Third downs could be more of a challenge for the 49ers with Crabtree out. He ranked fifth in the league last year with 22 catches that converted third downs into first downs. And he was second in third-and-seven or longer situations with 11 catches, behind Indianapolis' Reggie Wayne, who had 12.
Boldin led the Ravens with 16 catches that converted third downs to first downs, with eight in third-and-long situations.
"Even if it doesn't look like I'm open, just give me a chance," Boldin said he tells his quarterbacks. "I'll make a play for you."
Those quarterbacks responded to that message Tuesday, with all four completing at least one throw to Boldin and rookie B.J. Daniels rifling a touchdown pass to him.
"They did a good job of going through those reads," Boldin said. "It was one of those days where it happened to be me. It's not always like that. Another day, it might be another receiver. Today was just one of those days."