MINNEAPOLIS -- Adam Thielen was in the process of stringing together another near-flawless performance, which had become the norm for the Minnesota Vikings receiver during his first eight games of the season. And with just over a minute to play until halftime of a 30-20 loss to the New Orleans Saints, everything started to come undone.

The Vikings were riding high throughout the first half of their rematch of January's NFC divisional playoffs, with quarterback Kirk Cousins carving up the Saints' secondary and utilizing his top two weapons, Thielen and Stefon Diggs, to do so.

After crossing into the red zone late in the first half, leading New Orleans by three, Cousins had Thielen in the slot and saw the Saints giving the Pro Bowl receiver a 10-yard cushion. It was a matchup he knew Thielen could win.

Thielen was wide open to receive a screen pass from Cousins and had the end zone in sight. Upon being hit by two Saints defenders at the 14-yard line, Thielen coughed up the ball -- his first lost fumble of the season and the Vikings' seventh, tied for the fourth-most in the NFL. New Orleans cornerback Marshon Lattimore recovered Thielen’s fumble and ran the ball 54 yards in the other direction.

"That's probably the biggest reason we lost the game," Thielen said. "When you have the momentum going into the half, going to score points in the second half, that's a huge play. It can't happen."

Thielen's costly mistake delivered a huge blow, but it didn't have to be the dagger. On Lattimore's return, Minnesota receiver Laquon Treadwell let his temper flare and was hit with unsportsmanlike conduct after slamming his helmet into the ground after he tackled the cornerback at the Vikings' 33-yard line, which then moved the Saints to Minnesota's 18. Two plays later, New Orleans running back Alvin Kamara was in for a touchdown.

"That's something I haven't done," Treadwell said of his penalty. "It's an emotional game and I have to control my emotions."

Costly blunders, self-inflicted wounds and atypical errors haunted the Vikings on "Sunday Night Football," and it started with the mistake they made when they were 14 yards away from scoring before halftime.

Minnesota would get a shot at redemption after the Saints' touchdown. With 30 seconds remaining in the second quarter and two timeouts left (the Vikings lost their third timeout four plays into the game when Mike Zimmer lost a challenge), Minnesota ran one play -- a 7-yard rush by Mike Boone -- and decided to run out the clock instead of taking one last shot at the end zone.

Zimmer acknowledged his decision not to try and drive the ball down the field with 30 seconds left was affected by the fumble.

At the time, Cousins was 5-of-5 for 75 yards when targeting Thielen and 4-of-4 for 54 yards and a TD when targeting Diggs. Instead, the Vikings went into halftime trailing by four.

Coming out of the half, the Vikings still appeared shaken by how the second quarter ended. On Minnesota's first drive in the third quarter, Cousins was nearly picked off by Saints linebacker Manti Te'o and failed to complete a pass to Treadwell on fourth-and-1 from Minnesota's 45-yard line. While Treadwell was covered over the middle of the field by Lattimore, Cousins had two wide open reads with Thielen and Aldrick Robinson.

The Vikings' downward spiral didn't stop there. Upon getting the ball back the following drive, Cousins threw an interception, which was returned 45 yards for a touchdown by none other than P.J. Williams, the cornerback Cousins picked apart in the first half.

On the play, Diggs appeared to stop on his route, which the wide receiver shouldered the blame for postgame.

"[Cousins] was under duress and I was trying to give him a relief throw just because the pocket was collapsing and I was trying to show him my hands and he just did what he's coached to do, threw it to the spot," Diggs said. "Miscommunication, and I take full responsibility. He did everything right. It was all me."

Asked about the same play, Cousins noted he was "just playing to play fast" and said he would discuss what happened with Diggs and how to fix things "internally."

While the Vikings opted for a more conservative approach at the end of the first half, they chose to be aggressive on fourth down, converting on two of three attempts, each of which resulted in touchdowns.

"I told the team that I was going to be aggressive and that every fourth down that was close, we were going to go for it," Zimmer said.

Thielen's late chance at redemption, a 1-yard touchdown executed on fourth-and-1 with 5:09 to play, couldn't get the Vikings close enough to make a serious play at a win. The receiver became the first player to go over 100 yards receiving in each of his team's first eight games and tied Calvin Johnson in 2012 for the most consecutive 100-yard receiving games with eight.

Costly mistakes created a snowball effect for Minnesota, and in the end, it was too much to overcome. Not even a miracle could have saved the Vikings from their own demise in Week 8.

"We beat ourselves," Thielen said. "All credit to them, though. That is a really good football team. They made a lot of plays and they were able to capitalize on the turnovers. That's how this league works. Usually the team who wins the turnover battle wins the game."