For at least one night, the postgame clubhouse laughter was an earned mixture of youthful enthusiasm and veteran relief.

One by one, some of the young Mariners hitters who’d helped secure this 5-4 comeback win in 10 innings over the Chicago Cubs took their turns sharing the interview spotlight. And as they did so, the veterans who’d also made Friday’s win possible sat back and watched with an air of detached amusement.

The Mariners haven’t had many of these wins where players both young and older do their part. But a bases-loaded single in the 10th by Mike Zunino on a full-count fastball capped a day his franchise hoped would spark a revival for a club looking all-but-done by the season’s halfway mark.

“It’s one of those things where you have to be patient,’’ Zunino said of that final at-bat against Cubs relief pitcher Shawn Camp. “But it’s one of those things where I felt it was a very comfortable at-bat.’’

Comfortable, because he made Camp do the work and didn’t chase pitches. He took a 2-2 pitch to send the count full, then was ready for the fastball he sensed was coming.

“He kept coming with the fastball,’’ Zunino said. “So with a 3-2 count, I knew I had to stay aggressive.’’

And that he did, ripping it up the middle and past a drawn-in infield. The crowd of 31,471 at Safeco Field erupted as the Mariners poured from their dugout and put a pounding on the first-year catcher.

“Oh, man, and couple of rib shots and some slaps on the back,’’ Zunino said of the welcoming committee that greeted him in the infield. “But it was definitely worth it at that point.’’

For far too long, it seemed debatable whether all the pregame moves made by the Mariners had been worth it. They’d taken Brad Miller and Dustin Ackley straight out of Class AAA and stuck them in at shortstop and center field, respectively, in an attempt to add offense to a lineup that looked pitiful against Pittsburgh earlier this week.

The Mariners didn’t do much through the first 61 / 3 innings against Cubs starter Travis Wood. He had a 4-1 lead by the seventh inning after Alfonso Soriano and Dioner Navarro both went deep for solo homers that frame off Mariners starter Hisashi Iwakuma.

Jason Bay had the only Seattle score to that point, his solo home run in the fifth accounting for one of three Mariners hits off Wood. But then came the seventh, when a Bay walk and a Zunino double past two charging outfielders allowed Miller to knock in his first run with a ground out to the right side.

Then, in the eighth, Nick Franklin led things off with a double against Cubs reliever James Russell, followed by a Kendrys Morales RBI double that drew the Mariners within a run.