Sam Bradford isn’t a stopgap. Not just a rental quarterback.

He’s also not a top-tier quarterback worth a first-round pick under normal circumstances, either.

This isn’t a normal circumstance.

The Vikings made a bold but necessary move by trading a first-round pick in 2017 and a provisional fourth-rounder in 2018 to Philadelphia to acquire Bradford, a former No. 1 overall pick.

General Manager Rick Spielman’s willingness to pay such a heavy price for a quarterback with Bradford’s so-so résumé and injury history provides some insight into the Vikings’ immediate and long-term thinking.

The move shows the Vikings still believe they can contend this season without Teddy Bridge­water. They have a top-five defense and Adrian Peterson coming off a rushing title.

That alone could make the Vikings a playoff team. They won the NFC North last season with that formula and Bridgewater as a game manager.

The Vikings envisioned more this season — as a team and from Bridgewater — and his devastating knee injury this week rocked the organization to its core. Team officials had to sort through that disappointment and uncertainty for a plan that appeared to have only bad options.

Mike Zimmer has been unwavering since Bridgewater’s injury that he believes in his team. No excuses, he kept saying. The Vikings weren’t content to squeak by with a patchwork arrangement at quarterback.

The organization couldn’t afford to gamble that Shaun Hill and some fourth-tier quarterback signed off the street would not sink the hopes of this team. NFL seasons can’t be wasted, even when the franchise quarterback suffers a potentially career-altering injury.

That’s the other important element to this move: Bridgewater’s long-term future. The trade signals that the Vikings are concerned about Bridgewater’s ability to return next season, or perhaps beyond.

He didn’t just suffer a torn ACL. The damage to his left knee is extensive. It’s impossible to predict how his recovery process will go, or whether he will return the same player. That’s too much uncertainty to leave to chance.

Bradford provides a two-year bridge for Bridgewater to rehab while the Vikings, in theory, get competent quarterback play.

Does the cost for Bradford bring sticker shock? Absolutely, but the Vikings weren’t operating from a position of strength. They had no leverage. Teams understood their desperation.

If the Vikings still believe that they’re Super Bowl contenders, they could not move forward with Hill as the permanent starter. He’s a backup, at best.

This doesn’t guarantee that Bradford will provide what they’re counting on, but he gives them a better chance than a piecemeal approach at the most important position.

Bradford is not being hailed as a savior. Let’s be clear on that. He owns a career quarterback rating of 81.0 and hasn’t come close to fulfilling the expectation of a No. 1 overall pick.

The Vikings won’t ask Bradford to be something he’s not. He’s not stepping into a desolate situation where he’s required to carry a franchise. He will be surrounded by Peterson, an emerging Jerick McKinnon, a capable receiving corps and a top-shelf defense.

Bradford’s health history creates some concern and adds a touch of irony to this deal. He suffered a torn ACL twice with the St. Louis Rams, the second one causing him to miss the 2014 season.

Still, Bradford was probably the best option available under difficult circumstances. Spielman told reporters Thursday night that teams were asking for “some crazy things” in trade talks.

“People think that you’re desperate,” he said. “And we’re not going to do something that — in my estimation and [after] talking with Coach Zim and our ownership — puts us in a situation where we jeopardize the future of this franchise.”

Critics of this move undoubtedly will blast it as an act of desperation. News flash: The Vikings were desperate.

They are built to win now. Peterson is 31 and won’t stay at his elite level forever. The defense is legit. Opportunities to contend aren’t guaranteed every season. The Vikings can’t afford to wait around and see if Bridgewater fully recovers.

Parting with a first-round pick is expensive, but other options weren’t all that appealing. Felt like picking through clothes at a garage sale.

Bridgewater’s injury forced their hand, both for this season and with the future in mind. This is the best possible outcome considering the situation.