LAS VEGAS, Nev. — Fernando Mendoza did much to impress in his preseason debut. The rookie quarterback played a clean game in the team’s 27-14 loss to the Arizona Cardinals.Mendoza led the Raiders down the field on his second possession, finishing the drive with his first professional touchdown (albeit in exhibition action), connecting with receiver Jack Bech in the end zone for a six-yard score. He then completed four straight passes on his final drive to push the Raiders into the red zone before narrowly missing receiver Deven Thompkins for another TD.“I see an ascending player,” head coach Klint Kubiak said of Mendoza postgame. “We’ve just got to keep getting better.”Mendoza finished 10-of-16 for 97 yards and a touchdown. His connection with fellow rookie Malik Benson — off a play-action dropback and through three defenders — displayed the arm talent necessary for NFL throws and showed his ability to play from under center. Finding poise to throw a touchdown a few plays after running into a sack also showed the resiliency that’s needed to play the position at this level.“He did a great job,” quarterback Kirk Cousins said. “He moved the football, he scored points, gave us a chance to score points and operated well.”Top Plays from Cardinals @ RaidersMendoza, however, chose not to relish in his highlights.“Unfortunately, I let my teammates down today,” Mendoza said. “But it’s a growing experience. I feel like we’re all growing and it helped me show that I need to grow a lot.”The top pick of April’s NFL Draft has brought nothing but positive energy since arriving in Las Vegas. But at the end of an evening that served, in part, as a celebration of the franchise’s new era, he chose to focus on his faults.