The first two offseasons of the Mike Zimmer era were all about defense.

In 2014, General Manager Rick Spielman helped him fortify his defensive line with defensive end Everson Griffen and nose tackle Linval Joseph. Last spring, the Vikings used their first three draft picks on athletic, young defenders.

This offseason, though, their clear focus was improving Teddy Bridgewater’s supporting cast after Zimmer’s defense pulled the Vikings and their 29th-ranked offense as far as they could go — the wild-card round of the playoffs — in 2015.

“Because we have addressed the defense pretty heavily over the past two years and — those guys are contributing to help us win games — we focused a little bit more on the offensive side of the ball to help our young quarterback,” Spielman said.

The Vikings moved quickly in free agency to sign feisty left guard Alex Boone to a four-year, $26.8 million deal. Two weeks later, they added big right tackle Andre Smith, giving them nine linemen with at least 16 career starts.

They said goodbye to deep-threat Mike Wallace, a misfit in Minnesota who averaged 12.1 yards and about $253,846 per catch in his only season here.

And Thursday, they used their first-round pick on Mississippi’s Laquon Treadwell, a physical possession receiver who made contested catches in college and just so happens to be the best run-blocking wideout in his class.

While success cannot be measured until the NFL season starts, those moves, in addition to the natural progression of Bridgewater, give hope that the Vikings offense will close some ground on the defense in 2016.

“Spielman has done very well in this offseason,” Bleacher Report analyst Matt Miller said. “Adding two starting-caliber — and at times high-level — linemen was a clutch move. And then to add Treadwell in Round One shows that the Vikings are committed to giving Bridgewater the tools he needs.”

Expectations for Treadwell

Treadwell, who bounced back from a gruesome leg injury in 2014 to lead the SEC in receiving yards and receiving touchdowns in 2015, was not the fastest receiver in this draft class. That might explain why he was the fourth one drafted this year, surprisingly dropping to the Vikings at No. 23 overall.

But offensive coordinator Norv Turner said Friday morning on KFAN 100.3 FM that he feels Treadwell was “the most complete receiver in the draft.”

“Laquon is an awesome addition. He’s a physical, physical player. He fits our style of football,” Turner said. “I had a couple of guys text me [Thursday night] and say, ‘Hey, this is the type of player that fits what you guys do.’ ”

Reactions to the selection were mostly positive. NFL Network draft analyst Mike Mayock said after the pick was made that “the Vikings got a winner.” CBS Sports columnist Pete Prisco gave the Vikings an “A” for the pick and compared Treadwell to Pro Bowl wide receiver Dez Bryant of the Dallas Cowboys. Miller said he loves how Treadwell fits in Turner’s offense.

“He’s exactly what myself and many others have been asking for in that offense,” Miller said. “He’s a big, physical wide receiver that can win at the catch point.”

But while the Vikings believe the 20-year-old Treadwell will be a consistent chain-mover in the split end role that neither Cordarrelle Patterson nor Charles Johnson ran away with, Pro Football Focus analyst Steve Palazzolo questioned whether Treadwell can get open down the field.

“The problem with Treadwell is creating separation at the intermediate and deep level, right where Turner is trying to get the ball,” Palazzolo said. “In addition to not separating well, his pairing with Teddy Bridgewater is not ideal as Bridgewater is hesitant to throw into tight windows.”

Since the 2015 season ended, Turner and the Vikings have been encouraging Bridgewater to “let it loose.” Consider that missive heard loud and clear.

“I definitely get the message about taking more opportunities, taking more shots,” Bridgewater said last week. “And when they’re there, we just have to hit them.”

Balance wanted on offense

The addition of Treadwell should help a passing game that ranked 31st in the league last season. But Zimmer and the Vikings believe better blocking from an underperforming offensive line will do more for Bridgewater’s development in his third season than adding a new go-to receiver.

After all, it is hard for a quarterback to hit those open receivers when he is frequently forced to flee the pocket. Last season, Bridgewater was pressured on a league-high 46.9 percent of his dropbacks, according to Pro Football Focus.

And even though tailback Adrian Peterson led the NFL in rushing yards, the Vikings lament the yards left on the field because of blown run blocks.

Former NFL offensive lineman Brad Hopkins, now an analyst for SiriusXM, believes Boone and Smith will help prop their offensive line back up.

“Those guys will create the holes necessary to keep the run game effective and keep you out of third-and-long situations,” said Hopkins, who was a two-time Pro Bowl offensive lineman. “And they’re pretty good in pass protection, too.”

He also praised the addition of respected offensive line coach Tony Sparano, whom he feels will bring accountability and attitude to that position group.

On Saturday, the Vikings made Sparano’s meeting room even more crowded by drafting Western Michigan lineman Willie Beavers in the fourth round.

Despite the addition of Treadwell to the Vikings passing attack, Hopkins believes Peterson will remain one of the NFL’s busiest running backs in 2016.

“With Peterson, they’re still going to try to establish that menacing ground game, and then Bridgewater is going to complement that,” Hopkins said.

But the Vikings do hope to find a better balance between Bridgewater and Peterson, and not just in terms of their pass-to-run ratio. They have suggested that their hope to again try to mesh Peterson’s downhill running with the shotgun spread attack Bridgewater prefers. Of course, that was the plan in 2015, too, but it got scrapped after Peterson struggled out of the shotgun early in the season.

‘We’ve … done a great job’

Turner, by nature, isn’t a man who exudes enthusiasm. But by his subdued standards, he sounded pretty pumped about this ofseason.

“We’ve obviously done a great job, Rick and Zim, of [addressing] the needs we had,” Turner said Friday in his KFAN interview. “We added to our offensive line. We’ve created great competition there. We added Laquon.”

And during Saturday’s sixth round, they added German wide receiver Moritz Boehringer, an intriguing prospect who has limited experience but oodles of athleticism, and University of Texas at San Antonio tight end David Morgan.

But Turner also believes the players already on the roster must get better, too, for the Vikings offense to significantly improve from where it was in 2015, when it ranked 29th in total yards and 16th in points.

That especially applies to Bridgewater, who made the Pro Bowl as an injury fill-in in his second NFL season despite ranking 17th in yards per attempt.

With improved blocking up front and Treadwell inserted into his receiving corps, Bridgewater should have all he needs to take a leap forward in 2016.

“With some of the moves we made on the offensive line, with some of the receivers we’ve added, they’ll just help in the development of Teddy,” Spielman said.