Raiders quarterback Derek Carr left Thursday night's game against the Chargers after injuring his groin on a scramble.Las Vegas Quinndary Weatherspoon Jersey coach Jon Gruden believesthe injury is serious.Carr began limping as he completed the third-downplay late in the first quarter. He then walked to Las Vegas' locker room as the Raiders kicked a field goal to cut their deficit to 7-3.Raiders QB Derek Carr came up limping on this scramble. He is now walking to the locker room. FOX Sports: NFL ( Rudy Gay Jersey @NFLonFOX) "I don't believe it's a real tear," Gruden told reporters. "But obviously if he can't finish the game it's got to be pretty significant."Backup QB Marcus Mariota took over the Las Vegas offense with Carr out. This wasMariota's first appearance for the Raiders since signing a two-year contract with them in the offseason. He spent the first five seasons of his NFL career with the Titans after being drafted second overall by Tenne see out of Oregon in 2015.RAIDERS-CHARGERS: Mariota threw a 35-yard touchdown pa s to tight end Darren Waller on his first drive, part of a 5-for-5 pa sing performance in the first half.Mariota finished the night 17 for 28 for 226 yards, with one San Antonio Spurs T-Shirts touchdown and one interception. He also rushed nine times for 88 yards and a score.He led Las Vegas (7-7) to a go-ahead field goal on the first series of overtime, but the Chargers (5-9) responded with a Justin Herbert 1-yard touchdown on a quarterback sneak to win 30-27.Mariota became the first QB to have 200-plus pa sing yards and 75-plus rushing yards despite not starting the San Antonio Spurs Hats game since M.C. Reynolds in 1958."It just shows the kind of player, the kind of football character he has," Gruden said. "Our offensive coordinator Greg Olson isn't here, either. You lose Derek and then we changed gears offensively and Marcus came Tony Parker Jersey in and did a great job and I'm really proud of him."I think that this kind of puts an exclamation point on why we signed him and just wish we could've won the game for him."