The Los Angeles Chargers had a strong first half against the Las Vegas Raiders, but the offense may find things a bit more difficult in the second half. Star wide receiver Keenan Allen was ruled out for the remainder of the game after he picked up a hamstring injury during the first half of the game. Allen went to the locker room where he was examined by the training staff before the Chargers announced shortly after halftime that he would not be returning to the game.

Allen had initially been considered questionable to return after sustaining his hamstring injury but the Chargers opted against bringing him back out in the second half. The exact severity of the injury is unclear, but it's certainly worrying to see that he won't be returning to action in a close game against a division rival.

Prior to his exit, Keenan Allen had been the Chargers' most involved receiver. He caught four passes for 66 yards during the first half, leading all Chargers receivers in both categories. Justin Herbert had been enjoying going to his reliable veteran receiver, but that won't be the case during the second half with Allen making way due to his hamstring.

Chargers fans will be hoping that Allen can get back in time for the Week 2 matchup against the Kansas City Chiefs. He'll be up against the clock, h0wever, as they place on a short week of rest with their game slated for Thursday night. Losing Allen for that game would be another big blow for the team, who starts off the season with two key divisional games.

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