Cornerback Casey Hayward's recurring hamstring injury is so severe that he is expected to miss at least the Green Bay Packers' first four games. A source close to Hayward said the second-year player doesn't expect to play in the first month of the season. Hayward was declared out of the San Francisco early in the week. "I don't really have a time line for Casey" coach Mike McCarthy said Wednesday. "I hope his status is different next week." Hayward injured the hamstring in July working out in Atlanta before training camp. After sitting out what Hayward said was a month he joined practice Aug. 19. He worked two days in shells and Aug. 21 in pads. Position coach Joe Whitt hoped to play Hayward 15 snaps Aug. 23 against Seattle. He intercepted a deflected pass in the second quarter but then had to depart after just 10 snaps because McCarthy said he had reinjured the same hamstring. That was two weeks ago. Since then Hayward has been seen observing at practice but hasn't spent much time in the locker room when reporters are present. Hayward will be helped because the Packers' bye comes after the third game. It's possible he might be in position to return Oct. 6 against Detroit. But after what happened in the Seattle game you can expect the team's medical staff to be more cautious than usual. Last season Hayward led the Packers in turnover-producing plays with seven as the nickel back. He was the first Packers' cornerback to make the all-rookie team. Rookie Micah Hyde has assumed the job as nickel back. Uncertain: Meanwhile two starters on the Packers defense who have recently returned from hamstring injuries inside linebacker Brad Jones and safety Morgan Burnett are listed as questionable for Sunday's game at San Francisco. McCarthy said the two players came into Friday's practice with soreness. The two originally injured their hamstrings in Green Bay's exhibition finale Aug. 29 at Kansas City. "We'll see how it goes being smart with those guys" McCarthy said. "And really talking about the whole team you get to that point of 48 hours and it's important for everybody to get themselves ready to play the game." At safety the starters would be M.D. Jennings and Jerron McMillian if Burnett cannot go. Robert Francois would likely assume Jones' role. All camp Jennings and McMillian had been competing for the starting spot next to Burnett. Coaches have given the two a chance to work together as well. Still losing Burnett's communication skills would be a blow.