SANTA CLARA, Calif. (AP) - Jon Baldwin watched from the other sideline Friday night as Colin Kaepernick zipped warm-up passes to his wide receivers, then Baldwin marveled with a couple of Kansas City teammates about the do-everything 49ers quarterback.

Fast forward four days and, by lunchtime Tuesday, Baldwin had already caught 15 balls from Kaepernick while playing for his new team. San Francisco acquired Baldwin from the Chiefs on Monday for fellow underachieving former first-round draft pick and wideout A.J. Jenkins.

It's kind of funny because before the game I was watching him in warm-ups and I was saying, `He throws a pretty good ball,''' Baldwin said of Kaepernick.And I was talking to some of the other receivers about it on our team - I mean when I was in Kansas City - and they were saying, `Yeah, he did throw a pretty good ball.' And two or three days later, I'm here. It's kind of funny how things work out. It's a blessing in disguise and I'm looking forward to this great opportunity to be here.''

Baldwin passed his physical late Monday then went to work at 7 a.m. Tuesday with meetings and practice. He quickly made it a point to meet Anquan Boldin, someone Baldwin knows will be a valuable resource as he quickly tries to grasp yet a fourth offense in three years.

The 49ers are counting on him getting up to speed in a hurry as the two-time defending NFC West champions prepare for a far more daunting schedule as they try to return to the Super Bowl after falling three points short of a sixth championship against Baltimore last season.

Offensive coordinator Greg Roman said Baldwin's transition could go more smoothly given the fact he is going from one version of the West Coast offense to another, with similar language.

At 6-foot-4, Baldwin stood out in the locker room Tuesday not just for being the new guy. He certainly gives Kaepernick a tall target more comparable to Randy Moss than the injured Michael Crabtree or departed Jenkins, who failed to catch one pass during a highly scrutinized rookie season last year.

He hit the ground running this morning at 7 a.m. He's been diving into it,'' Roman said of Baldwin.Speaking of Jonathan the player, size is the first thing you notice when you look at him. He's got really good range, leaping ability. We saw that when we studied him. A great catch radius is always a great thing. There's nothing wrong with having a great catch radius.''

Baldwin has something to prove, along with several others in the mix to make the team and pick up some of the load left with the absence of Crabtree, last year's top receiver. Crabtree is recovering from surgery on his torn right Achilles tendon and is likely to be sidelined until at least November.

Roman isn't ready to guess how the receiving corps will line up for the Sept. 8 season opener against Green Bay at Candlestick Park.

We'll see how it all shakes down. It's heavy competition right now,'' Roman said.You can see it. It's like preparing for a regular season game. It's very evident.''

Baldwin has 41 career catches in 26 games with two touchdowns. Kansas City selected him 26th overall in the 2011 NFL draft out of Pittsburgh.

He didn't have a catch while being targeted three times for Kansas City in the Chiefs' 15-13 home loss to San Francisco. Baldwin dropped one would-be catch.

The 24-year-old Baldwin has learned to ignore the critics, and he is welcoming this new opportunity.

People are going to have their own reasons for thinking that way. I can't change the way people think. As human beings we can't make everybody happy,'' Baldwin said.The only thing I can do now is look forward to the future and look forward to the present. ... It's a fresh start. I've just got to do what all these coaches need me to do and be real precise with things from that standpoint, just soak all of it in. Be around Anquan and learn a lot of things from him. He's been in the league for a long time and knows all the ins and outs.''

And Roman made it clear he expects his young players to learn from the experienced veterans.

If I was a young player and I didn't do that I would want somebody to just smack me in the head,'' he said.If you're a young player and you don't take advantage of that, we need to have a talk.''

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