OXNARD, Calif. - The Cowboys breathed a huge sigh of relief Friday afternoon when owner and general manager Jerry Jones announced the preliminary results on Marcus Spears' knee injury were not as bad as initially feared. Spears is expected to miss as much as four weeks with a mid-grade sprain of the medial collateral ligament in his right knee, Jones said. Spears, taken to a local hospital for an MRI and X-rays, also suffered a high-ankle sprain and a strained calf muscle Friday morning. "There's a chance he'll be back for the opening game of the season (at San Diego,...