San Francisco 49ers at Las Vegas Raiders

A rough night for Raiders rookie Fernando Mendoza in 18-12 preseason loss to the 49ers

“It's the NFL, there are monsters on the other side of the ball and you need to get the ball out quick,” Mendoza said. “It teaches you, you need to play on time, and there's less margin for error. So I think it's a great experience having that heat and duress because diamonds are built under pressure.”

Mendoza completed 7 of 14 passes for 57 yards, making him 25 of 40 for 240 yards with a touchdown, two interceptions and four sacks for the three preseason games. He led five drives against the 49ers, one ending in a field goal and another in the missed attempt.

It wasn't quite the exclamation point the top overall draft pick wanted to put on the preseason, and now he will have to search for practice repetitions with Kirk Cousins expected to be the starter when the season begins. Cousins took the vast majority of snaps in training camp for the Raiders (1-2), who now go full time into game planning.

“(Mendoza) needs another three preseason games, and all those rookies do," Raiders coach Klint Kubiak said. “Now that the season is starting, the practice reps get smaller and that's just life. But us as coaches, we've got to get them ready to play and keep developing.”

Both coaches took notably different approaches to this preseason finale, with Kubiak playing almost his entire starting offense and defense for two series and the Niners' Kyle Shanahan going with backups the entire game.

Now both coaches have serious decisions to make before the rosters are cut to 53 on Sunday.

“I’m looking forward to figuring out exactly our final team here over these next three days," Shanahan said. "We got a lot of tough decisions; they’re not easy ones. I want to see how the practice squad pans out and really what our opening day roster is going to be. I just like when the season starts. Preseason gets a little bit old, and I like when it gets real and it’s going to get real, real fast.”

Cousins directed two drives, both ending in field goals. He completed 8 of 11 passes for 51 yards.

Mike Washington Jr., who could open the season as the starting running back with Ashton Jeanty out with an undisclosed injury. rushed for 49 yards on eight carries. Washington rushed for 168 yards in the preseason, averaging 7.3 per carry.

49ers backup quarterback Mac Jones and what was mostly the second-team offense was held to one first down and 20 yards on two drives against the Raiders' starting defense, minus pass rusher Maxx Crosby who didn't play in any preseason games. Jones finished 1 of 5 for 7 yards.

The Raiders went with Mendoza for the third period and gave him the starting offense, except for rookie Trey Zuhn III taking over for Tyler Linderbaum at center. Mendoza threw high to Jalen Nailor on his second play, and the ball popped into the air into the hands of San Francisco linebacker Tatum Bethune for an interception.

Injury report 49ers: CB Ephesians Prysock (shoulder) and TE Brayden Willis (concussion) were injured. LB Jalen Graham was evaluated for a concussion and cleared.

Raiders: DE Keyron Crawford (ankle) was hurt late in the third quarter.

Up next 49ers: Open Sept. 10 against the Los Angeles Rams in Melbourne, Australia.

Raiders: Open Sept. 13 against Miami at home.

See AP’s full NFL coverage here

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