Kenneth Murray Jr.'s interception on the final pass of the Vikings' loss to the Chargers played on an endless loop, in exquisite and excruciating detail, as T.J. Hockenson searched for sleep Sunday night.

On his drive home from U.S. Bank Stadium after the four-point loss, Kirk Cousins agonized over where he would put the ball on a pass to K.J. Osborn that would have kept the interception off Hockenson's hands from ever happening.

Mistakes and missed chances linger in the minds of Vikings players and coaches these days, as a team that won 11 one-score games a year ago is now one of only four winless clubs in the NFL. The plays that gnaw at them the longest might be the ones that happen closest to the end zone.

The Vikings have lost all three of their games by six points or fewer, with a turnover at the goal line in each of them and a handful of red-zone misfires in two. A year ago, the Vikings were eighth in the NFL in red-zone efficiency, turning 62.5% of their trips inside the 20-yard line into touchdowns. This season, they've scored touchdowns on only 50% of their red-zone trips, which ranks 21st in the league.

Even though the Vikings scored on all three of their trips into the red zone against the Eagles, Justin Jefferson's fumble, as he reached for the goal line following a 30-yard gain, went through the end zone for a turnover that had the receiver yelling in frustration in the locker room after the game. Against the Buccaneers, the Vikings went 1-for-3 in the red zone, and they were 1-for-4 against the Chargers. Their seven red-zone trips in those two games yielded two touchdowns, two field goals, two interceptions and a turnover on downs.

"You're never going to play perfect. But whenever there's plays to be made, you expect to go make them," Cousins said. "We made a lot of plays. We're making a lot of plays. A lot of plays. But when you have a high standard, there's always going to be a few more you wish you'd made."

The Vikings' effort to improve their red-zone production comes as they prepare to face the man who did so much of his best work for them near the goal line. Adam Thielen, whose 34 red-zone receiving touchdowns trailed only Davante Adams and Travis Kelce over the past five years, signed a three-year, $25 million deal with the Panthers this offseason after his celebrated 10-year run in Minnesota ended with his release in March.

During his five years with Thielen, Cousins targeted him in the red zone 79 times. He caught 61 of those passes, for a 77.2% catch rate that topped any Vikings receiver with more than two targets in that time. This season, Thielen has been the Panthers' leading receiver through three games, catching 20 passes on 25 targets while playing with No. 1 overall pick Bryce Young and veteran Andy Dalton. Both of his touchdowns this season came in the red zone.

"Adam has always done a great job of separating with tight coverage, using his body to create space," Cousins said. "I always have felt like coaches have done a great job with red-zone concepts of creating reads for me where Adam was getting open. I was throwing to the open guy, and it happened to be Adam. So, I've got to give coaches a lot of credit and give Adam a lot of credit for being open. There were a few one-handed catches down there, and double moves and things that he made, tight windows where he's just being the great receiver that he is."

Thielen said this week he will head to the field for pregame warmups earlier than usual on Sunday, giving himself extra time to catch up with former teammates, coaches and team officials before facing the Vikings as an opponent for the first time.

He is part of a team also looking for its first win this season, but while the Panthers could be afforded some patience with a new coaching staff and quarterback this season, the Vikings are 2 ½ games behind in a division they won by four games last year.

Their urgency, to coax more production out of an offense that ranks third in the league in yards but only 15th in points, is at a high level this week.

"I think when you're younger, you're a little bit more willing to shrug your shoulders and know there's more games up ahead," Cousins said. "I think when you're older, you're like, 'It's now. It's got to be now.' I was saying that last year, too: 'The Adam Thielens won't be here forever. Let's do it now.' "

Why not just throw it to Jefferson?

The Vikings' issues in the red zone were especially troubling in the 28-24 loss to the Chargers, when each facet of the offense could point to problems that took away potential touchdowns.

When a double-team on Jefferson led to Alexander Mattison running open across the formation in the second quarter, Joey Bosa hit Cousins' arm and caused his pass to wobble short of the running back. Mattison was stuffed for a 1-yard loss at the goal line when the Vikings had a chance to take the lead in the fourth quarter. Jefferson was flagged for an illegal shift two plays later when he didn't set his feet before the snap, and Hockenson said he might have been too quick to get to his spot up the hash mark on Cousins' final pass, allowing linebacker Nick Niemann to squeeze the quarterback's throwing lane.

"If we run the football down there, things are condensed. You have to be that much more physical," coach Kevin O'Connell said. "You have to be that much more willing to sell out as you get closer to the goal line, to not allow penetration and potentially a negative run. And then when we play pass, we're trying to attack certain things. When those looks present themselves, we have to throw and protect, throw and catch.

"And then on those third downs, it's all 11 guys doing their job, whether you're the quarterback taking the right footwork and the right reads [or] the receiver's details. Maybe it's the O-line understanding we're going to have five in protection and this is the down we have to strain and give our quarterback one hitch to try to manipulate [the defense]."

Offensive coordinator Wes Phillips cautioned those who say, "Just throw it to Justin." The Vikings have come to expect frequent double-teams on Jefferson, who has a 50% catch rate in the red zone in his career (62 targets) and this season (4). He doesn't have a red-zone score this season, and he said he sees the most exotic coverages from other teams near the goal line.

Phillips pointed to the Mattison pass as a play where the attention on Jefferson created an opening, only for Bosa's pressure to short-circuit it.

"Because he was doubled, that meant that everyone else was singled, and we were able to get a nice rub [route] and get a guy open," Phillips said. "That's kind of what we wanted. Ultimately, there's a lot of factors that go into it. I understand that people look at it probably a lot and say, 'Just throw it to Justin,' right? But with a condensed space, if they are going to commit two players, it can be a little more challenging than that."

'Forced to prove it'

The increased attention on Jefferson might have helped Thielen in the red zone during his final seasons in Minnesota, but as the Vikings talked about releasing him for cap reasons this offseason, Thielen indicated he wanted a chance to prove he could still succeed as a featured player in an offense at age 33.

He signed with the Panthers, preparing to play football outside Minnesota for the first time in his life. When he arrived in Charlotte, he said, everything from a new set of schools for his kids to the help he needed navigating Bank of America Stadium's layout made him feel like a rookie again.

"When you're in a new place, you're forced to prove it every day," Thielen said. "When you've been in the same place for 10 years, it's not necessarily that you're forced to prove it. Even if that's your mindset, sometimes it gets to the point where you have it in the back of your mind that everyone knows what you can do. When you're forced to prove it, it makes you home in and focus, so that part's been good for me."

He knows Vikings fans will travel to Charlotte, and he will look forward to the purple No. 19 jerseys in the stands. And then he'll go to work, against former teammates trying to rekindle the kind of production they had during Thielen's final season in Minnesota.

"I would be lying to you if I said I'm still not thinking about a couple of things here and there," O'Connell said. "It's kind of the could've, would've, should've type thing. I am trying to use a lot of that to move forward the right way."