The Seahawks could be without rookie Russell Okung for a while after he left Saturday night's preseason game with an ankle injury. The left tackle was recently given a guaranteed $27 million as the sixth overall pick in April's NFL Draft. He will have an MRI to reveal the extent of his high right ankle sprain. Similar injuries can take weeks to heal. "It's pretty significant," head coach Pete Carroll said. "Obviously we made it as big a priority as we could make it to get him."