SEATTLE — The future is staring the Yankees in the face.

They had better pay attention to what they see. Playing Jacoby Ellsbury in center field is a waste of time right now. Slide Brett Gardner to center, let Clint Frazier play left with Aaron Judge in right field and go from there.

Gardner came through when the Yankees needed him most Thursday night at Safeco Field, driving a solo home run to right-center with one out in the sixth for the first run of the game as the Yankees came away with a much-needed 4-1 win over the Mariners.

Judge knocked in the second run in the eighth with a bases-loaded single to right, and the Yankees scored two more in the ninth on a throwing error by Robinson Cano.

Here is what Gardner means to the growth of young outfielders like Judge and Frazier:

“Gardner has got gold,’’ Judge told The Post. “Any information you can get from him you get, you just have to find that nugget.’’

Gardner said he’s just following the lead of the veterans who came before him.

“It’s kind of hard to believe I’ve been around as long as I have, but it’s just about embracing the situation, and I have,’’ Gardner said. “All the guys before me, whether it be Derek [Jeter], Johnny Damon or Jason Giambi, I remember how they were to me as a young player and I am returning that favor.

“That’s part of the game,’’ Gardner added. “The more comfortable these guys feel in the clubhouse and on the field, the better we are going to play as a team.’’

That the home run came against Felix Hernandez was even more impressive. This isn’t the same old King Felix, but on this night Hernandez had allowed just one hit, an anti-shift single to left by Chase Headley in the third inning until Gardner took him deep.

Gardner’s home run traveled 406 feet and was his 16th of the season, more than doubling his home run count from last season and one shy of equaling his career high set in 2014.

Frazier got a seat on the bench to get Ellsbury in the game, but the Yankees need to play their best players every day.

Despite all the money the Yankees owe Ellsbury, he is a fourth outfielder. Ellsbury batted eighth — the first time he has batted eighth with the Yankees — and went 0-for-4, extending his slump to a 6-for-42 skid. He has just four homers this season.

Gardner, 34, has those 16 home runs over his last 71 games. He is the Yankees’ longest-tenured player and deserves the everyday opportunity to work with Judge and Frazier and help guide them.

In Judge and Frazier, the Yankees have a pair of rookie outfielders who could be teammates for years, two players this generation of Yankee fans could love. After David Robertson arrived and took back his No. 30, Frazier now wears No. 77; Judge wears No. 99.

It is a fun, cool, new-school look for the outfielders.

In 1960, when the Yankees had outfielders Mickey Mantle and Roger Maris, the M&M Boys were strong together for years. Mantle wore No. 7; Maris wore No. 9.

With No. 99 and No. 77, it is a much different era of outfielder for the Yankees — and in no way am I comparing Judge and Frazier to Mantle and Maris, but the numbers do evoke a link to those two magical numbers.

Those two Yankees numbers, 7 and 9, are retired, of course.

Judge already has his own chambers at Yankee Stadium. Frazier is in the feeling-out process of his career, but has made incredible strides since being called up. Since debuting on July 1, Frazier is batting .298 with six runs, three doubles, two triples, three home runs and eight RBIs in his first 13 games, the most hits for any player to debut this season over his first 13 games.

Wouldn’t it be something if Nos. 99 and 77 continue to develop and have a major impact on the Yankees and a generation of fans for years?

But for that to happen, the Yankees need to play Frazier and Judge — with Gardner — and let it roll.