LAS VEGAS – Kellen Mond took the fourth-down shotgun snap, standing placidly in the pocket as the Raiders sent a three-man rush after him. He saw Dan Chisena — one of his secondary options on the play — shake free from cornerback Chris Jones on a deep out route, and Mond flicked the ball to the receiver for a 22-yard gain.

"That was the decisiveness: His first progression was taken away, quiet in the pocket, just progressed in rhythm and threw an absolute beautiful ball to Dan," coach Kevin O'Connell said. "And then you saw him getting to his third and fourth progressions, late [in the game] there to Jalen Nailor [for 16 yards] or Myron [Mitchell for 16 yards] on the backside [of the play]. When you see him getting back to that, that's growth."

Contrast that with Mond's final throw of the first half in the Vikings' 26-20 loss to the Raiders in the preseason opener: He scrambled left, then right, evading a three-man rush as his teammates, first Bisi Johnson and Trishton Jackson, then Ihmir Smith-Marsette and Zach Davidson, put their hands up to call for the ball. Mond threw behind Jackson and out the back of the end zone as Smith-Marsette put his hands on his helmet, and O'Connell called for his second short Greg Joseph field goal, after a play where he thought Mond had a chance for a touchdown.

O'Connell approached his first preseason game, his initial rite of passage as the 10th coach in Vikings history, with two goals: Keep core starters healthy and learn as much as he could about the young players who would take the field at Allegiant Stadium on Sunday.

The first objective was easy, with all of the Vikings' Pro Bowl skill players and five defensive starters not playing. If O'Connell could claim he succeeded in the second, it might be because of experiences like the one Mond had.

"I wanted to come out and win this game," O'Connell said, "but we're going to make sure we don't miss an opportunity to have some real teachable moments."

The Vikings lost because of their inability to finish drives in the first half and some defensive lapses throughout; they gave up two long-second half scoring drives and allowed the Raiders to hold the ball for the final 3 minutes, 44 seconds. But in some dynamic moments from young running backs Ty Chandler and Kene Nwangwu, flashes from defenders like Brian Asamoah and Patrick Jones and especially in Mond's second half, the Vikings might be able to latch onto something.

Mond threw two second-half TD passes to Albert Wilson, finishing 9-for-14 for 119 yards. Sean Mannion, who played the first three series and returned for one more in the fourth quarter, went 8 of 12 for 79 yards.

The Vikings outgained the Raiders 172-94 in the first half, but incurred 66 penalty yards. They went 0-for-4 on third downs, and got just six points out of their two red zone trips.

Mannion overshot Ihmir Smith-Marsette in the back corner of the end zone on the Vikings' third drive, and O'Connell opted to send Joseph in for a 20-yard attempt.

"My thought process was, 'I can leave the ball high and safe, and we have points in hand with a great kicker,' " Mannion said. "I got a little bit too careful; we've got other people in the play, if I can just move on there. Maybe there's something and maybe there's not, but any time you're in the red zone, you want to come away with seven."

On Mond's first series, the Vikings ran five times for 54 yards, with Chandler displaying the elusiveness he's showed in camp to extend runs that started with big holes up the middle. Nwangwu bounced outside for 12 yards, before Mond missed Johnson on a fade, and after a 2-yard run Nwangwu run, the Vikings had to call on Joseph again after Mond's missed third-down connection.

"I saw Kene on the right side," Mond said. "It's one of those where I probably gave the corner a little bit too much credit; his hips were a little bit more down the field, and I thought he could still make a break on the ball. As you look back on it, obviously it's easy to coach yourself whenever you come back to the sideline and you watch it on video. Those are some of those things where you continue to train your eyes, and have a little bit more confidence in ripping those things."

Las Vegas, which led 10-6 at the half, extended the lead to 10 points when Nick Mullens hit DJ Turner for a 34-yard touchdown on a drive where the Vikings' illegal substitution penalty on a punt gave the Raiders a first down.

Mullens fit his third-down TD pass over a shallow drop from linebacker Blake Lynch as Turner beat Parry Nickerson across the field. Nickerson tried unsuccessfully to strip the ball, and Turner eluded rookie Akayleb Evans while safety Josh Metellus got blocked.

"Ultimately, can we get better situationally?" O'Connell said. "Third down and red zone just weren't good enough for us to win."

They headed home, after their first-ever game in the state of Nevada, hoping they forged out some progress.

"It's just continuing to stack days and continuing to get better," Mond said. "I felt a lot more comfortable as I continued to go on."