NAPA, Calif. (AP) - A year ago, Mario Henderson was so raw that he wasn't even considered an option to start at left tackle for the Oakland Raiders no matter how desperate they were to fill that gaping hole.
Now following an injury to free agent acquisition Khalif Barnes, Henderson is the only option the Raiders have at that crucial position.
What once would have been a frightening proposition for the Raiders is now a viable one following a strong finish to last season that built both Henderson's confidence and the team's belief in him.
"You knew that he had a talent but maturity-wise he has really grown," said coach Tom Cable, who rode Henderson hard as his position coach the past two seasons. "He has worked so hard and has really changed who he was early in his career."
The Raiders traded for the pick to select Henderson in the third round out of Florida State in the 2007 draft. He was immediately labeled a project after starting just one season in college.
His progress was slow and he got caught in between the feud between former coach Lane Kiffin and Raiders owner Al Davis. Kiffin mockingly referred to Henderson as "Super Mario" and sarcastically talked about how "interesting" it would be to watch Henderson try to block Tennessee's Kyle Vanden Bosch in an exhibition game last summer. When Kwame Harris struggled during training camp last year, Kiffin said he had no other options at the position, dismissing the idea that Henderson was ready to play in
"I'm not going to say it was too harsh," Henderson said. "I'm going to take the blame. Maybe I wasn't doing what they were expecting of me. I took that as motivation. ... I was going to show them that one day they would be able to count on me and just show them that I can play in the league."
Cable wasn't much easier on Henderson after he took over as interim coach four games into last season. Hesitant to criticize players in public, Cable went after Henderson after he struggled at Miami while splitting time with Harris.
"I guess they were trying to make him tougher because you've got to be a tough dude to play left tackle," tight end Zach Miller said. "You're seeing all the great defensive ends in the NFL every week and you really have to be able to bounce back if you give up a sack or that sort of thing. I think they were trying to harden him a little bit."
Henderson appeared in only one game on special teams as a rookie in 2007 before getting his chance to play last season. He played briefly early in the season when Harris was hurt, but the Raiders mostly ran away from his side of the field and gave him extra help in pass protection.
As Harris struggled throughout the season, Henderson got another chance only to be benched again by Cable. Henderson finally got his shot in the final three games of the season and more than held his own against some tough competition.
Facing New England's Richard Seymour, Houston's Mario Williams and Tampa Bay's Gaines Adams, Henderson did not allow a single sack or commit a penalty as Oakland won two of three to end the season.
"I learned a lot," Henderson said. "When I wasn't playing, I'd do a lot more film study. I had started two games earlier so because I knew they were going to be depending on me, I think I studied more. It's like a child. Every day you grow up. That's kind of like what I do."
Henderson came into camp with a slight edge in his battle with Barnes for the starting left tackle spot. But after Barnes went down last week with a broken left ankle, the job was all Henderson's.
And Henderson's confidence has just continued to grow. His teammates have noticed the difference this training camp, seeing a completely different player than the one who was in Napa the past two summers.
"He was just nervous and afraid to mess up," Miller said. "Now he's not afraid of making calls, making dummy calls and messing with the defense so it's good to see. ... He's a totally different guy than when he was a rookie. It's a good thing because we need to play well at left tackle."
NOTES: First-round pick Darrius Heyward-Bey missed the team portion of practice with a sore toe. Heyward-Bey spent most of the session catching passes from Danny Southwick, who is an intern with the team after spending OTAs as a quarterback on the roster. Cablesaid the injury wasn't serious. ... WR Johnnie Lee Higgins also missed practice with tightness in his leg.