NAPA -- The Raiders were blindsided Wednesday with the news that left tackle Jared Veldheer would need surgery on his left triceps and miss a significant amount of time.
Coach Dennis Allen said it's conceivable Veldheer could be placed on injured reserve but designated for return, which would leave the Raiders without their best offensive lineman for a minimum of seven games.
"I don't know what the timetable is going to be," Allen said. "The hope is we're going to be able to have him back at some point this year."
Following practice, during which Alex Barron took first-team snaps at left tackle, Veldheer spoke with his linemates but declined comment to the media through a team spokesman.
"He was disappointed," Barron said. "As a team and teammates we're disappointed for him. You never want a guy to get hurt or injuries that require time out or surgery."
Veldheer missed practice Tuesday to have an MRI, his second in 10 days. After the MRI on Aug. 3, Veldheer returned to practice wearing a brace on his left arm and didn't miss a session until deciding to get a second opinion.
Allen said Veldheer did not further injure the arm by practicing and considered surgery the best option.
"After sitting down and visiting with Jared, visiting with the doctors, we decided we're going to go ahead and get it fixed," Allen said.
Teams are allowed to have one player on injured reserve who is designated for return, a provision that requires the player to miss six weeks, then return for two weeks before being able to play.
Veldheer would be included on the original 53-man roster before going on injured reserve, with the Raiders then being able to sign another player.
"We'll have to see how everything goes (with the surgery)," Allen said. "We can make that decision at a later time."
Assuming Veldheer goes on injured reserve and is designated for return, the best-case scenario would be to have him return Nov. 3 against the Philadelphia Eagles in the eighth game of the season.
At 6-foot-8, 321 pounds, Veldheer came into camp believing he was in the best shape of his life with the help of a grueling weight training regimen that he said made him stronger, faster and quicker than he'd ever been.
Veldheer has started 42 straight games while missing only one offensive snap. His loss is huge for a unit that is unsettled at both guard spots and has yet to see its second-round draft pick, Menelik Watson, make it through a practice session because of a calf injury.
"It's one of the positions that is tough to lose -- especially being a quarterback," quarterback Matt Flynn said. "We have guys who have to step up and guys that are playing well. We'll get it figured out, but it's very tough to lose a guy like that."
Barron is a veteran of 87 NFL games and 75 starts but hasn't played since 2010, when he was a reserve tackle for the Dallas Cowboys. A first-round draft pick for the St. Louis Rams in 2005, Barron was considered inconsistent and penalty prone, amassing 13 false starts in 2006 alone.
He spent time in camps with New Orleans in 2011 and Seattle last year and didn't make either team.
"I basically looked at coming here as an opportunity," Barron said. "What happened before was a reality. It was a reality check. It was what it was. I just looked forward during the summer and OTAs to come to camp to do what I need to do."
Flynn, who was with the Seahawks last season when Barron failed to make the team, said, "He seems like a different guy here. He's playing really well and coming into his own."
Said Allen: "It will be a great opportunity for him, and we'll see what he does with it."
Aside from Watson, who has made it through only a few drills in one practice last week, other tackles on the roster include John Wetzel, an undrafted rookie out of Boston College, and Willie Smith, who struggled in seven starts last season when veteran Khalif Barnes was lost to groin surgery.
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