Generation upon generation of Vikings fans have spent more than half a century wondering when that doggone oblong-shaped ball will bounce their way both figuratively and literally.

Now, halfway through their 58th season, a high-priced Vikings team built to end a 42-year Super Bowl drought is 4-3-1, has lost the turnover battle five times and is muddling along in a tightly packed NFC North Division that features no five-game winner and four teams within a game of each other.

“No one in this division is ever really out of it at this time of year,” Vikings wide receiver Adam Thielen said. “This probably will come down to the last few weeks.”

Defense of the division title finally begins in earnest for the Vikings on Sunday, when they kick off a stretch of division games that includes three in a row and five of the final eight.

“It is a unique schedule,” quarterback Kirk Cousins said. “Schedules can be different. They’re not all created equally, but I guess it gives us a great opportunity in the second half of the season to have a lot to play for.”

First up is Detroit (3-4), which is looking to go to 3-0 at U.S. Bank Stadium. A victory for the Lions also would mark the first time since 1991-93 that they have won four times in five games vs. the Vikings.

“We’ve always had good games against them,” said Vikings coach Mike Zimmer, who is 3-5 against Detroit, including 1-3 at home. “And they’ve always been a good team when we’ve played them.”

Turnovers, turnovers

The Vikings went to four of the first 11 Super Bowls. Their turnover differential: minus-12 (15-3). And, as you know, they went 0-4 while being outscored by 53 points.

Twenty years ago, they were 16-1 when they were favored at home against the Falcons in the NFC title game. The beginning of the end that day started when Randall Cunningham fumbled the ball away inside his 20-yard line in the closing minutes of the first half.

In 2009, the Vikings pushed the Saints up and down the Superdome field. But they also lost the turnover battle 5-1, and the game in overtime.

Last year’s NFC Championship Game at Philadelphia started with a 7-0 lead. A pick-six made it 7-7. Two more turnovers contributed to a 38-7 loss.

This year, the Vikings were favored by 16 ½ points at home against the Bills in Week 3. Two turnovers in six plays handed Buffalo a 17-0 lead en route to a 27-6 rout.

Last week’s prime-time game against the Saints opened with a celebration of last year’s “Minneapolis Miracle.” It ended with the miracle maker, Stefon Diggs, literally getting in line behind Thielen to apologize for their parts in two turnovers that created a potential 21-point swing.

And now here come the Lions, whose five wins over Zimmer have come by a total of 32 points.

Against Chicago, Zimmer is 6-2 with a plus-9 turnover differential. Against the Packers, he’s 4-4-1 and minus-2. But against the Lions, he’s 3-5 in large part because his team has lost the turnover battle five times and is minus-5 overall.

“The times we’ve lost to them,” said Thielen, “we’ve generally struggled with turnovers and not playing well on third down.”

Last year at home, the Vikings held Detroit to 251 yards and seven punts while sacking Matthew Stafford six times. But they lost 14-7 because two turnovers led to 11 points while the third and final one — a fumble by Thielen — clinched the loss with 1:43 left and the Vikings past midfield.

From Van Brocklin to Tice

The Vikings are 72-39-2 (.646) against the Lions, including 39-16-1 (.705) at home. But, once upon a time, the Lions were an unbeatable force for the Vikings.

On Nov. 19, 1961, Detroit pounded the expansion team 37-10 in front of 44,509 fans at Met Stadium. The Lions won the next four meetings and were 8-3-1 against coach Norm Van Brocklin. Five decades later, the Dutchman’s .292 winning percentage against the Lions remains the worst among the nine Vikings coaches. Even Les Steckel (1-1).

Things changed once Harry Peter “Bud” Grant arrived from Canada on March 10, 1967. The volatile Van Brocklin gave way to the steely blue eyes of authority and calm, well- organized leadership.

“What made Bud such a great coach was his unique style of saying nothing,” former Vikings defensive end Bob Lurtsema said. “Just one look from Bud would maintain your 110 percent effort.”

No team felt the wrath of Bud’s blunt-force team like the Lions. After starting 0-1-1 vs. Detroit, the Hall of Famer went on to post a 26-8-1 mark that included 15-1-1 at home.

And yet that’s still not the best percentage against the Lions. During their particularly anemic decade of the 2000s, the Lions went 0-8 against Mike Tice (1.000) and 1-8 against Brad Childress (. 889).

Stafford arrives in ’09

Stafford arrived in Detroit as the first overall pick of the draft in 2009. As a rookie, he lost twice to the Brett Favre-led Vikings. He didn’t face the Vikings in 2010, went 3-3 against Leslie Frazier and is 5-3 against Zimmer.

In 16 games against the Vikings, Stafford is 8-8 while completing 62.3 percent of his passes for 3,993 yards, 23 touchdowns, seven interceptions and an 89.2 passer rating.

Now a 10-year veteran, Stafford is backed by a strong running game for the first time in his career. The defense is struggling, particularly against the run, but the Lions and new coach Matt Patricia have found a way to go 2-0 against Tom Brady and Aaron Rodgers.

Stafford posted identical passer ratings of 101.9 in those two big wins.

“I believe just being in the league over the years, he’s learned from his mistakes,” Vikings cornerback Xavier Rhodes said. “You learn not to force things. You learn to look at film and realize what you can and cannot do. He’s basically playing smarter than he has in previous years.”

Zimmer also sees a more cerebral Stafford, albeit one who still has the huge arm strength and a scrambling ability that Zimmer said would make “Fran [Tarkenton] happy.”

“I think one of the areas he’s gotten better at is the red zone,” Zimmer said. “He had thrown a lot of turnovers in the red zone in the past. He’s taking good care of the football now.”

And that’s a big deal, as any Vikings fan from baby boomer to Gen Xer knows from experience.