This one seemed a bit stunning, and it turned as quickly as a 101-mph fastball from Aroldis Chapman.

Cubs manager Joe Maddon was more than willing to delve into the machinations of Saturday’s interesting 4-1 loss to the Seattle Mariners at Wrigley Field.

On a cool afternoon, perfect for pitchers, the Cubs had just chiseled out a 1-0 lead against Mariners starter Wade Miley in the seventh inning, the same inning in which they recorded their first hit.

They did it with a walk, a single, a sacrifice bunt and a run-scoring fielder’s choice, getting help from a replay review that reversed an out call on Dexter Fowler at home plate.

Cubs ace Jake Arrieta took the mound for the eighth, having thrown 89 pitches but without significant stress.

But Arrieta walked the Nos. 7 and 8 hitters, prompting Maddon to go to setup man and erstwhile closer Hector Rondon.

A sac bunt moved the runners ahead, and Cubs third baseman Kris Bryant threw out runner Guillermo Heredia at the plate, with replay confirming the call.

So far, so good for the Cubs.

With left-handed batter Leonys Martin coming up, Maddon went to lefty closer Chapman, trying to get him his second four-out save since the Cubs acquired him this week.

Martin had other plans, as he lined a double to the gap in left-center to score 2 runs. He then stole third base and came home on a Chapman wild pitch. The Mariners added 1 in the ninth.

“It really comes down to the two walks,” Maddon said. “Jake was in such good position right there with 89 pitches. That started the whole inning up. We almost escaped it. I give Martin credit. He squared up a 100-mile-an-hour fastball and put it in the gap. That just tells you how good he is.”

Chapman had not had a four-out save with the Yankees before coming to the Cubs, but Maddon is as likely to make that move as not.

“That part of that (Seattle) batting order just yells his name,” Maddon said of Chapman. “That’s the whole point. To go through that moment, if he’s available, and to not utilize him and then lose the game, I’d have been really upset again with myself. Getting away from the traditional methods that have gone on more recently, it’s hard to not (use Chapman) unless he’s totally unavailable for four outs and is only available for three.”

Chapman credited Martin for getting the hit.

“Of course,” he said through translator Pedro Strop, a Cubs reliever. “Every hitter is just coming there to try to do their job. It was my time to lose this time.”

Asked how he felt about coming in for four-out saves, Chapman replied, through Strop: “It’s not my favorite thing to do, but that’s my job ... I’m just ready to do anything.”

Arrieta was charged with the loss, as he fell to 12-5 with a 2.75 ERA. He got credit for a quality start, with 2 runs allowed in 7 innings, but he has not won a decision since June 27.

“You can nitpick a couple things, but obviously the eighth inning didn’t do us any favors,” he said. “There were a couple pitches to (Mike) Zunino that could have gone either way (that were called balls on a walk). I tried to execute them in a very similar spot in that at-bat. Just didn’t do a very good job to the next guy (walk to Shawn O’Malley). But again, we’re moving in the right direction.”