FILE – In this Aug. 9, 2018, file photo, San Francisco 49ers quarterback Jimmy Garoppolo looks for a receiver during the team’s NFL preseason football game against the Dallas Cowboys in Santa Clara, Calif. The Niners acquired Garoppolo before the trade deadline from New England. After a few weeks to learn the offense, Garoppolo stepped in and showed why the Patriots had groomed him as Tom Brady’s successor. (AP Photo/Josie Lepe, File)
FILE – In this Aug. 9, 2018, file photo, San Francisco 49ers quarterback Jimmy Garoppolo looks for a receiver during the team’s NFL preseason football game against the Dallas Cowboys in Santa Clara, Calif. The
… more Photo: Josie Lepe / Associated Press
It’s time for 49ers vs. Vikings: the matchup between the quarterback Kyle Shanahan lucked into and the quarterback he lost.
When Shanahan was hired in February 2017, the 49ers’ head coach was hopeful and fairly confident he would land Kirk Cousins, a Pro Bowl QB with whom he worked in Washington, during the 2018 offseason.
But a funny thing happened on the way to a reunion: After the trade for Jimmy Garoppolo fell into the 49ers’ lap, he led them to a 5-0 finish and signed a $137.5 million contract extension in February.
How enamored was Shanahan with Cousins? This offseason, general manager John Lynch said Shanahan didn’t completely rule out signing Cousins even after the 49ers had acquired Garoppolo. But the likelihood that the 49ers had just committed to Garoppolo — and not Cousins — to be their man initially had Shanahan “in mourning,” Lynch joked to ESPN Radio.
On Wednesday, in advance of Sunday’s season opener at Minnesota — which signed Cousins to a three-year, $84 million fully guaranteed contract in March — Shanahan was asked: Did he ever tell Lynch how funny his comment was?
The Minnesota Vikings are set to open their season Sunday against the San Francisco 49ers, but with a different center snapping to brand new quarterback Kirk Cousins
“I told him how bad of a choice of words that was,” Shanahan said, smiling. “But, no I understood what he was trying to say. I have a lot of respect for Kirk and I think he’s in a very good situation and went to a very good place …
“I’m extremely happy with who we have here, and where we’re at, and the decision that we made on who to go with.”
Jimmy G completely made up play he scored touchdown on vs. Jags 49ers’ McGlinchey born to protect, on and off the field Injuries deplete 49ers’ linebacker corps
Sunday’s game won’t be a referendum on the 49ers’ decision. Even if he’s outplayed by his counterpart, Garoppolo, 26, is four years younger than Cousins and his performance during his 7-0 start to his career suggests he could join the NFL’s elite.
However, the opener will provide the first look at what might be possible in 2018 for the 49ers. Garoppolo’s presence has made them a popular playoff pick after a 6-10 season, and a win at U.S. Bank Stadium would elevate expectations significantly.
The Vikings have swapped Case Keenum for Cousins after a 13-3 season in which they reached the NFC Championship Game. On defense, they return 10 of 11 starters from the league’s top-ranked unit and their new face is Pro Bowl defensive tackle Sheldon Richardson. Minnesota has won nine of its past 10 home games.
“This is what you want to start the season,” 49ers right guard Mike Person said. “You’ll know exactly where you’re at. You’re playing one of the best, if not the best, defense in the NFL. It will be a good litmus test for us. It will be our first chance to see where we are as a team and what we can do.”
Cousins credits Shanahan for much of what he has been able to do in his seven-year career. In the past three seasons, Cousins, a 2012 fourth-round pick, has thrown 81 touchdown passes, 36 interceptions and averaged 4,392 passing yards.
We “could be here a long time (discussing) how Kyle developed me as a player,” Cousins told reporters. “I don’t know that the answer would do it justice.”
49ers at Vikings
Where: MinneapolisWhen: 10 a.m.
TV/Radio: Channel: 2Channel: 40/810, 107.7
Spotlight on: RB Alfred Morris. Was his 17-carry, 84-yard preseason performance against the Colts’ squishy defense a harbinger or a mirage? The answer to that question became much more important after the preseason loss of starting RB Jerick McKinnon to a torn ACL. In fairness, Morris’ first real test is daunting: Last year, the Vikings allowed the second-fewest rushing yards in the NFL.
Injuries: 49ers — OLB Dekoda Watson (hamstring) was placed on injured reserve Saturday, a day after he was injured in practice; ILB Malcom Smith (hamstring) is questionable. Vikings — Starting C Pat Elflein (ankle, shoulder) is out and Brett Jones, a 13-game starter with the Giants in 2017, likely will assume his spot; CB Xavier Rhodes (hamstring) is questionable.
What to watch for
The 49ers enter with the NFL’s longest current regular-season winning streak (5 games).
With a win, Jimmy Garoppolo — the 49ers’ fourth season-opening starting QB in the past four seasons — would become the third QB since 1970 to win his first eight career starts (Ben Roethlisberger 15; Mike Tomczak 10).
The 49ers, who are opening on the road for the first time since 2014, have won six of their past seven season openers.
— Eric Branch
Last year, Cousins and Shanahan reconnected when Washington beat the 49ers 26-24. The game, played 15 days before the acquisition of Garoppolo, came during a time when Shanahan figured there was a “strong possibility” the 49ers would sign Cousins in the offseason.
Shanahan’s not mourning the loss of Plan A.
“I think we fell into another alternative option,” Shanahan said, “that was pretty darn good.”
Eric Branch is a San Francisco Chronicle staff writer. Email: email@example.com Twitter: @Eric_Branch