EAGAN — For all the mistakes the Minnesota Vikings made to waste a significant amount of their good work in the season opener, the feeling was strong on their sideline — and throughout the stadium, for that matter — that they would ultimately extract a victory from a tight game.

The Vikings turned that into an art form last year, after all, setting an NFL record with 11 wins in 11 decisions by eight points or fewer.

This time, those vital fourth-quarter plays just weren’t made.

“There’s an unwavering belief in this locker room. Even when there’s five minutes left and we were down by a field goal, we thought we had that one for sure,” tight end T.J. Hockenson said.

The offense went three-and-out on its last two possessions. The defense allowed a fourth-down conversion to extend Tampa Bay’s drive for the tiebreaking field goal and later let the Buccaneers drain the final 3:52 off the clock Sunday with a 15-yard facemask penalty and two third-down conversions for a 20-17 victory.

“We have to find a way to do something there whether it’s offense or defense,” safety Harrison Smith said. “We have too special of a group not to do something.”

The Vikings widely outgained the Buccaneers by an average of 5.9 to 3.6 yards per play, but their three first-half turnovers not only cost them a prime crack at two scores but gave Tampa Bay three easy points.

“A lot of credit to that team on the other side, but we beat ourselves,” running back Alexander Mattison said. “It’s hard to win a game that close when the turnover margin is three to zero. It’s one of those things we just have to make sure we clean up.”

That process has to happen quickly, because the Vikings play Thursday at Philadelphia.

“I’ve got nothing but confidence in our football team, and maybe even more so after watching the tape yesterday knowing how close things were to being maybe a different result,” coach Kevin O’Connell said.

WHAT’S WORKING

The connection between Kirk Cousins and Justin Jefferson — and the play calling by O’Connell that contributed to their potency — picked up where it left off last season. Eight different receivers caught passes, but four of the five completions by Cousins that topped 20 yards went to Jefferson.

WHAT NEEDS HELP

The blocking left much to be desired. The Buccaneers sent some well-timed blitzes at Cousins that weren’t picked up, most glaringly by safety Antoine Winfield Jr. on a strip-sack he recovered at the Minnesota 18. Mattison and Ty Chandler combined for just 34 yards on 14 carries.

“Efficiency is something we’re going to continue to strive for,” O’Connell said. “We did not get it done.”

STOCK UP

Jordan Addison became the seventh rookie in Vikings history to score in his NFL debut when he caught a 39-yard touchdown pass from Cousins in the second quarter. He had four receptions for 61 yards.

STOCK DOWN

Right guard Ed Ingram remains the starter on the offensive line of greatest concern. He accidentally caused one of the fumbles by Cousins when he tried to seal the nose tackle with a block to his left and knocked the ball out of the quarterback’s hand with his left arm to thwart a third-and-2 running play at the Tampa Bay 26 in the first quarter.

“I don’t know how that happened. That was some type of freak accident,” Ingram said.

KEY NUMBER

9 — That’s how many times Jefferson has gained at least 150 receiving yards in 51 career games, the second most in NFL history in a player’s first four years. If Jefferson gets there twice more this season he’ll break Lance Alworth’s record.

INJURY REPORT

The shortened week will make it tougher for center Garrett Bradbury to recover in time from the back injury that forced him out in the first quarter. O’Connell said Monday that Bradbury’s status was day to day and that he was “feeling pretty good.” He had a similar injury last season that cost him five games.

Left tackle Christian Darrisaw was able to return from an ankle injury that sidelined him during the first half. Outside linebacker Marcus Davenport also has an ankle injury that landed him on the inactive list. Both players were listed on the estimated Monday injury report as limited participants had the Vikings held a practice. Players had the day off.

NEXT STEPS

The Vikings, who lost in Week 2 at Philadelphia last year after winning their opener, don’t have much margin for further errors, given opening wins by Detroit and Green Bay and a daunting early schedule. Their next three home games are against the Los Angeles Chargers, Kansas City and San Francisco.