Aug. 14 (UPI) — Las Vegas Raiders quarterback Fernando Mendoza said he failed to meet his “standard” in his NFL preseason debut, a loss to the Arizona Cardinals.

Mendoza, the No. 1 overall pick in the 2026 NFL Draft, completed 10 of 16 passes for 97 yards in the 27-14 setback Thursday in Las Vegas. The 2025 Heisman Trophy winner and national champion also ran for six yards.

“Coach Andrew Janocko, coach Klint Kubiak and coach Mike Sullivan, they all have a very high standard and that’s a standard that I want to one day get to and that I know our entire offensive unit and team wants to get to and I did not meet that standard,” Mendoza told reporters.

Veteran quarterback Kirk Cousins, 37, started against the Cardinals, but played just one series. Mendoza, 22, was in for the next four. He logged incompletions on his first two attempts. Mendoza went on to connect with tight end Jack Bech for a 6-yard touchdown 3:13 before halftime.

Mendoza, who called the game an “invigorating experience,” cited necessary improvements for his timing, anticipation and reading of defenses. He also said NFL legend — and Raiders minority owner Tom Brady — provided advice Wednesday night.

“He said, ‘no matter how good of a high school or college player you were, the NFL is a different level,'” Mendoza said. “I felt that [Thursday night] and I have a lot to grow from.”

Kubiak previously said Cousins, who completed 5 of 6 passes for 50 yards and a score, would begin training camp as the Raiders’ starter. He confirmed Thursday that the role was Cousins’ “job to lose.”

Kubiak plans to get Mendoza increasing repetitions and experience throughout the preseason.

“I thought he led a good scoring drive,” Kubiak said. “As far as getting in and out of the huddle and commanding the group and getting the play calls down, I saw the same guy we’ve seen in practice.

“I see an ascending player. We’ve just got to keep getting better.”

Mendoza credited Cousins for his advice and called him a “master of his work.” He said he planned to watch game tape immediately after the Raiders’ preseason opener.

“Unfortunately, I let my teammates down, but it’s a growing experience,” Mendoza said. “I feel like we are all growing. It showed me that I need to grow a lot.”

Third-string quarterback Aidan O’Connell completed 4 of 13 passes for 85 yards in the loss. Raiders starting running back Ashton Jeanty ran for 16 yards on three carries.

Veteran quarterback Jacoby Brissett completed 5 of 5 passes for 44 yards and a score for the Cardinals. Gardner Minshew completed 14 of 16 passes for 101 yards and two scores in the win.

The Raiders will face the Houston Texans in their second preseason game at 8 p.m. EDT Thursday in Houston. They will host the San Francisco 49ers in their preseason finale Aug. 27 in Las Vegas. The Raiders will open the regular season against the Miami Dolphins on Sept. 13 in Las Vegas.

The Cardinals will host the Dallas Cowboys in their third preseason matchup Aug. 22 in Glendale, Ariz. They will battle the Green Bay Packers in their preseason finale Aug. 28 in Green Bay, Wis. The Cardinals will meet the Los Angeles Chargers in their regular-season opener Sept. 13 in Inglewood, Calif.