At 5-feet-10 and 186 pounds, Kyle Williams isn't the type of wide receiver NFL teams generally target on fade routes in the end zone.

Last week, however, the 49ers' preferred pass-catcher in such situations, Braylon Edwards, was sidelined by a knee injury and Williams was asked to do his best impression of his 6-3, 214-pound teammate.

On 3rd-and-3 at the Cowboys' 12-yard line, Williams, split wide left, broke off the line, saw the Dallas blitz and, moments later, the 23-year-old with one NFL catch saw the opportunity for No. 2 coming his way in the left corner of the end zone.

Blanketed by Cowboys cornerback Mike Jenkins, Williams soared high, snared Alex Smith's deftly placed pass and did a left-foot, right-foot tap dance to secure his first NFL touchdown.

No Edwards? No problem. At least for one memorable play.

"Obviously, the big touchdown catch Williams had was a great representation of the next man up," offensive coordinator Greg Roman said last week. "Somebody goes down, the next guy comes in and he has to be ready. And he was ready."

Williams, whose touchdown was his only catch in last week's loss to Dallas, is ready to assume a larger role as the 49ers visit the Bengals today. Edwards (torn meniscus) is out for several weeks and Michael Crabtree is listed as probable with a troublesome left foot. Williams, Joshua Morgan and Ted Ginn Jr. are San Francisco's only fully healthy wideouts.

Williams has his best opportunity to showcase his ability after an injury-marred rookie year. A sixth-round pick in the 2010 draft from Arizona State, Williams' first season featured a torn toe ligament, a broken finger and one catch for 8 yards. He wasn't guaranteed a roster spot in training camp but easily secured a job in the preseason with violent blocking that belied his size and team-highs in catches (seven) and yards (105).

Williams is the Niners' shiftiest receiver, but Smith and Crabtree highlighted his work ethic when asked about their teammate this week.

Ask Williams about his drive and he'll explain that it's a product of his unique childhood.

Williams' dad, Kenny Williams, is the general manager of the Chicago White Sox and has been part of that organization as a player, scout and front-office executive for most of the past 29 years.

So Kyle Williams, who wore a White Sox cap during an interview this week, grew up around a clubhouse. He says the memories of his annual, weeklong trips to spring training when he served as a batboy endure because he saw, firsthand, what it takes to become a professional athlete.

The typical wisdom all young athletes receive - be prepared, work hard, stay out of trouble - was lived out in front of him.

He fielded groundballs alongside his favorite player, second baseman Ray Durham. He played catch before games with Gold Glove shortstop Ozzie Guillen, now the team's manager. And he often sat quietly at the end of the bench next to designated hitter Harold Baines, a soft-spoken, six-time All-Star who played 22 seasons in the big leagues.

"It was an advantage," said Williams, who also starred in baseball growing up. "Just to see how these guys carried themselves. To see how pros went about being pros and the work that it took to get there. And through my dad, I also saw the minor-league side of it. I got to see behind closed doors that this guy might be better than this guy, but he has some character issues. So you don't want to be labeled one of those guys."

His dad made a point of highlighting the pros who did it right. And he also noted those who were wasting their talent.

It was no coincidence that Durham, a tireless worker, doubled as one of Kenny Williams' favorite players. Kyle recalls numerous occasions when his dad would discuss an anonymous minor leaguer in spring training who had the right stuff and would forecast future success.

"He'd point out the guys that were busting their tail, and he would be like, 'Hey, you see how he works. That's why he is where he is. That's why he's going to get where he's going to get,' " Williams said. "I can remember (White Sox shortstop) Alexei Ramirez. He told me about him years ago. He'd say, 'This guy - he's going to be a star in the major leagues. It's because he works. It's because he cares.' You get a lot of insight from being around that, and if you're smart, you'll listen."

Williams listened well enough to find himself in the left corner of the end zone against Dallas last week.

Given his size, Williams said he was a little surprised Smith threw a fade his way.

Given his background, though, it wasn't a surprise Williams was prepared to make the play.

Be ready when your number is called?

That's the type of wisdom he picked up years ago.