Last time the New Orleans Saints visited they aided and abetted the Minneapolis Miracle. Sunday night, they facilitated Minnesota mediocrity.

Midway through the 2018 season, the Vikings are 4-3-1. They have not beaten a team that currently owns a winning record. They are not in any kind of serious trouble, not while playing in a middling division, but they have failed to separate themselves from their competitors, and their performance on Sunday night did little to hint that they are prepared to do so.

Playing at home in front of a ridiculously loud crowd, the Vikings on Sunday fell to New Orleans 30-20 while failing to look well-coached, composed, organized or inspired, and even their best players let them down.

Adam Thielen continued to perform like one of the greatest receivers in NFL history, but his second-quarter fumble may have marked the turning point in what, during the first half, was a thrilling, back-and-forth game. "I'm definitely disappointed in myself," Thielen said.

Video (02:18) Adam Thielen had a key fumble in the second quarter that led to the Saints taking a lead they never gave up.

Laquon Treadwell dropped one important pass and earned an unsportsmanlike-conduct penalty that aided the Saints' touchdown following Thielen's fumble. If football kept a plus-minus statistic, Treadwell would not want to know.

Stefon Diggs produced like a star but acknowledged that he stopped running a route in the third quarter, leading Kirk Cousins to throw an interception that was returned for a touchdown. Give Diggs credit for taking "full responsibility."

Vikings coach Mike Zimmer wasted a challenge on the Saints' first drive, costing him a timeout and making him appear overeager, and then decided not to run a play with 30 seconds and two timeouts remaining in the half, even though he has an expensive quarterback and trailed at the time.

Asked whether the Thielen fumble influenced that decision, Zimmer said, curtly, "Yeah." That's the wrong answer when you have a veteran quarterback and two receivers and are playing against a prolific offense.

Zimmer also went for a first down on fourth-and-1 from his 45 on the first drive of the third quarter, and the Vikings turned the ball over on downs. Intelligent analytics support such a move, but it runs counter to the cautiousness Zimmer displayed at the end of the first half.

"I told the guys that we were going to be aggressive," Zimmer said.

But he may not have mentioned when.

The Vikings defense was missing cornerback Xavier Rhodes and linebacker Anthony Barr, gave up 30 points and was lucky that number wasn't higher. Saints back Alvin Kamara dropped a pass that could have produced a long touchdown in the first half, and the Saints looked content to run a ball-control passing offense once they had the lead rather than let Drew Brees unsheath one of the most productive arms in NFL history.

So while the Vikings were congratulating themselves on being a play or two away from winning, and being, as Zimmer and his players said, "a really good team," the Saints may have been one or two plays from making this a laugher.

At this time last season the Vikings, with a backup quarterback they would choose not to re-sign, were making the 2017 season feel like something special.

The 2018 season has never felt so easy or charmed, not since the missed kicks at Lambeau in Week 2 and the subsequent and nagging embarrassment at home to the woeful Buffalo Bills.

It's not that the Vikings are hopeless or doomed, just that instead of establishing themselves as one of the best in the league, they have mired themselves in the league's middle class, from whence they will need help and luck and improved health to change franchise history.

The 2018 Vikings have already matched the 2017 team's total for regular-season losses. That's not a death knell, but it may ring a few alarm bells for those who thought this team was destined to compete for a championship.

There may be a miracle in the Vikings' future, but this team was supposed to be good enough not to need one.

Jim Souhan's podcast can be heard at TalkNorth.com. On Twitter: @SouhanStrib. • jsouhan@startribune.com