Seahawk Garry Gilliam says he’s ready for the challenge of moving to left tackle

When Garry Gilliam headed to Manhattan Beach, Calif., for an off-season of training, he assumed he would be preparing for his second season as the Seahawks’ starter at right tackle in 2016.

But a phone call from offensive line coach Tom Cable a few weeks ago alerted him of a change in plans and a shift in roles.

With Russell Okung gone, having signed as a free agent with Denver, Cable told Gilliam the left tackle spot was essentially his to lose.

It’s a plan that was reiterated in a more recent conversation with coach Pete Carroll.

“When I got back up here (for the team’s voluntary off-season program that began this week) I talked to coach Carroll and he told me about the opportunity and the opening and if I was going to seize it,’’ said Gilliam Thursday night before he entered the El Gaucho restaurant in Bellevue, preparing to spend the night serving as a celebrity waiter for a benefit for Ben’s Fund. It’s a charity initiated by Seahawks general manager John Schneider that awards grants to help the financial needs of families who have children on the autism spectrum.

Gilliam said he told Carroll that “of course’’ he planned to do what it takes to win the left tackle job.

“He said he always saw me as a left tackle,’’ Gilliam said.

Many figured that if Okung didn’t return, the Seahawks might try to add a left tackle via trade or free agency. Seattle did sign Bradley Sowell, who started at left tackle for Arizona in 2013 and he is expected to compete with Gilliam. But Sowell, who got a one-year contract for $1 million, was hardly the blockbuster signing many expected.

And the Seahawks may well add a left tackle in the NFL draft next week.

But the team has also made clear to Gilliam that he is the front-runner to replace Okung, who had held the job since 2010 when he was the sixth overall pick of the draft and the first pick made in the Schneider/Carroll era.

“Obviously it’s a big role, especially for an offensive lineman to try to hold down that left tackle spot,’’ he said. “So yeah, I’m excited for it.

“I’m just going to keep going as planned and just keep working to get stronger in the off-season and work my head around that. Obviously there is going to be a competition there, as well as right tackle. Nothing is set in stone.’’

That the Seahawks did not make a big move to add a left tackle indicates a faith in the players on their roster that may not be universally shared after a season in which the offensive line was generally considered a weakness, something Gilliam said the players appreciate.

“Yeah, it shows the confidence they have in the guys that we have here in Seattle,’’ Gilliam said. “Obviously they would like me to be the left tackle and I’m going to seize the opportunity to do my best to sew that spot up.’’

Gilliam was Okung’s backup as a rookie in 2014 and early in training camp in 2015 before the Seahawks shuffled the line, moving Gilliam to starting right tackle.

At the NFL league meetings last month, Schneider reiterated the team’s belief that Gilliam can handle playing left tackle.

“He’s a heck of an athlete,’’ Schneider said. “He’s played there in college, too, and he’s just such a good athlete. He can play wherever you want. He can play tight end — you have seen him catch the ball (a reference to his touchdown on a fake field goal in the NFC title game win over Green Bay in 2015). He’s extremely talented.’’

Gilliam said he currently weighs 305 but wants to get to about 312 by the time the season starts. That would be down a bit from the 318 he said he weighed at the end of last season.

“I felt slow,’’ he said.

Shortly after getting the news that he would be moved to left tackle, Gilliam had dinner with the man he hopes to replace, Okung.

Okung’s advice?

“He said just have full confidence in knowing I have the ability to hold the spot down,’’ Gilliam said.