HOUSTON -- At an open tryout hosted by the Houston Astros, a baseball player confidently approached the registration table.

"What do I have to do to sign up?" the man asked. "I'm ready."

But this man wasn't carrying a glove and wearing cleats like the hundreds of players around him. That's because at 75 years old, Frank Robinson wrapped up his Hall of Fame playing career long ago.

Robinson was touring Houston's MLB Urban Youth Baseball Academy on Thursday morning and decided to give the aspiring players a few words of wisdom.

"Don't ever let anybody tell you that you can't be a great baseball player," Robinson said. "If you want to impress these scouts, you've got to give it your very best effort. You're going to come up short in some area, but you've got to put forth the effort to stand a chance."

Robinson's message resonated to Marcus Chandler, who sat feet away in the first row of the bleachers. Wearing a black Astros cap and a brick red Astros shirt, Chandler admits he wants to play professional baseball over anything else.

"It was such a blessing to have him here talking to us," Chandler said. "I honestly felt like he was talking directly to me because I've had so many setbacks in life, but I've never given up."

At any open tryout, youth and potential is everything. When the scout asked how many 15-year-olds were trying out, Chandler nervously looked around to see how many hands were raised. At 31, Chandler knew he had to perform better than spectacular.

The road to Thursday's tryout has been long and difficult for Chandler. He has random sprouts of gray hairs in his beard, and it has now been more than a decade since he was a 17th-round pick by the Kansas City Royals in 2001. After a promising start to his career, Chandler suffered a torn muscle in his forearm. Doctors told him he'd never throw a baseball again.

"I overcame that, and I feel like I'm ready for another shot," Chandler said. "Today is everything."

Chandler was stretching near the dugout when a burly man walked behind him. It was legendary Astros pitcher J.R. Richard, who was accompanying his 20-year-old son, James, an aspiring pitcher. Richard spent countless hours in the weeks leading up to the tryout, helping his son improve his velocity.

"You could say I used him as a guinea pig to get his speed up," Richard said. "I had a few theories, and they worked out very well -- I think he's ready for this."

As the second overall pick in the 1969 First-Year Player draft, with plenty of exposure out of high school, Richard never had to put his talents on display at a tryout. For Astros area scout Rusty Pendergrass, who oversees the entire state of Texas from Interstate 20, south to the Mexican border, talent is everything.

At an open tryout, Pendergrass said he looks for players who might have slipped through the cracks. Many of the players were recent high school graduates, junior college players or even former draftees, but everyone was trying to get on Pendergrass' watch list.

Some even impress him beyond making the watch list. He almost always introduces his tryouts with the story about the time he took a player directly from tryouts to sign a contract at Minute Maid Park.

"But the chances of that happening ... " Chandler said, lifting his hat to expose his balding head, "... are about the same chances as me growing a full head of hair. But give it your all, and good things can happen."