If new Raiders offensive T Willie Smith had any doubts about whether he belonged in the NFL, they ended in the final three games of his rookie season last year with Washington

Smith made the team as an undrafted rookie out of East Carolina. He was thrust into the starting lineup at left tackle when Trent Williams was suspended four games for failing multiple drug tests.

After coming off the bench and sharing time with Sean Locklear in Week 14 against New England, Smith started against the Giants, Vikings and Eagles. He lined up against New York’s Jason Pierre-Paul, Minnesota’s Jared Allen and Philadelphia’s Trent Cole, who combined for 49 ½ sacks last year.

“Every day you go in practice against Pro Bowl caliber guys,” Smith said. “I was going against (Brian) Orakpo and Ryan Kerrigan, and then you get in the game situations and you get to actually go against Jason Pierre-Paul and Jared Allen. It lets you know that, ‘Hey, I can do this. I’m good enough to go out there and play.’ So it was good for my confidence and allowed me to realize that I could go out there.”

The Raiders claimed the 6-foot-5, 310-pound Smith off waivers Saturday, one day after the Redskins released him.

“Athletic. Long arms. Comes from the same type of system so the learning curve shouldn’t be that difficult,” Raiders coach Dennis Allen said of Smith. 

Smith pointed to “athleticism” and “quickness” as the strengths of his game.

“Normally when you think of an offensive lineman, you think of a big, fat slow guy,” Smith said. “You get an athletic guy like me, it allows you to go out there and run the ball.”

Smith was shocked when the Redskins released him.

“But I was like, ‘Hey, I know somebody else is going to pick me up because I know I was a great player.’" Smith said. "I did some good things last year, and I improved this year.” 

Smith has already proven he can adapt to change. He played defensive line his first two seasons at East Carolina before moving to offense, initially as a tight end.

“‘Come over and play tight end and catch some balls.’ And then before you know it you’re playing tackle. They got me like that," Smith said. "It was the best decision I ever made because it got me into the NFL.”

Follow Raiders reporter Eric Gilmore on Twitter @CBSSportsNFLOAK.