SEATTLE >> You take the series win, certainly. But when a sweep seemed so imminently attainable, nearly in your grasp, it made for a more gloomy flight home.

“We didn’t do enough,” manager AJ Hinch said after the Tigers dropped the finale against the Mariners Wednesday, 3-2, at T-Mobile Park. “They got an opening with a couple of mistakes and they took advantage of it. It is frustrating. It’s a good series win, we’ll take that and head home.

“But this is a game we feel we could’ve won if we do one or two more things correctly.”

Start with a two-out mental mistake by second baseman Colt Keith in the second inning.

Tigers’ starter Tarik Skubal didn’t have a clean entry into this game. He allowed a two-out single and double to Cal Raleigh and Randy Arozarena in the first inning but escaped by overpowering Mitch Garver with a 98-mph heater.

Then in the second he walked Dylan Moore but seemed to be out of the inning when he got J.P. Crawford, the only left-handed hitter in the Mariners’ lineup, to hit a routine ground ball to Keith at second.

Keith fielded the ball on a short hop and, inexplicably, spun to throw to second even though there were two outs and Moore had just run right in front of him.

He abruptly pivoted and threw to first but the throw was late and the inning stayed alive.

“I tried to come in a get it with one hand and the hop beat me,” Keith said. “There no better word for it, I just kind of panicked. I knew how many outs there were. I opened up and for some reason turned all the way. It was a messed up play and it hurt us today.”

Leadoff hitter Victor Robles cashed in both runners, hitting a first-pitch changeup just over the outstretched glove of Ryan Kreidler in center.

“You can’t let things out of your control impact who you are on the mound,” Skubal said. “You have to continue to make pitches and I didn’t make a pitch (to Robles). We’re probably not even talking about it if I get the next guy. That’s on me. I will be better.”

The other run Skubal allowed came on a mislocated slider to Moore leading off the fourth. That ball ended up in the right-field seats, the third homer allowed by Skubal in his first two starts.

But after the Tigers scored twice in the top of the fifth to crawl back into the game, Skubal went into beast mode.

“I was able to execute to my glove side (getting his fastball in on right-handed hitters) a little bit more consistency than I’d been able to do the last five or six days,” he said. “Getting to the glove side is the key to my success. When I do that consistently, I’m really hard to hit.”

Witness the bottom of the fifth: He struck out the heart of the Seattle batting order — blowing high-octane heat past Julio Rodriguez (97-mph four-seam fastball), Raleigh (97-mph four-seam) and Arozarena (97-mph two-seam fastball).

A definitive power show by the reigning Cy Young winner. He got seven swings-and-misses out of those three at-bats.

“It’s just a mental thing,” he said. “It’s more mental than physical most times. It’s just staying behind the ball and driving it through there, instead of letting your body leak and letting the ball leak back over the plate.”

Skubal set down seven straight after Moore’s homer and he left with two outs in the sixth after walking Moore for the second time. He was at 93 pitches

“I thought it was more about getting his fastball to the glove side and making his pitches,” Hinch said. “He was yanking some changeups to right-handers and got burned with that a little bit. But he has to locate his fastball. Whatever it was that locked him back in, he got really good.”

The three walks were as uncharacteristic for Skubal as giving up three homers in two starts. A third of the hits he’s allowed (three of nine) have left the yard. But he still struck out eight with 23 misses on 52 swings. The Mariners put 14 balls in play against him with a mild 81.5 average exit velocity.

He pitched plenty well enough to win.

“It was competitive,” Skubal said. “We kept right in and I’m proud of our guys. We were going for the sweep and I would’ve loved to go home 3-3. But we won the series and that’s the most important thing.”

The Tigers’ offense was subdued for seven innings by Mariners starter and three-time All-Star Luis Castillo. The Tigers nicked him in the fifth. Trey Sweeney dropped the bat head on a slider down and in and drilled it into the right-field seats, his first homer of the season.

With one out, Kreidler singled and aggressively went to third on a single Zach McKinstry. Kreidler then made a keen read and scored on a tapper to third base by Riley Greene.

It got interesting in the ninth. Seattle closer Andres Munoz walked Keith (his third walk) and Justyn-Henry Malloy, and with one out, pinch-hitter Dillon Dingler hit a jam-shot single to left to load the bases.

Keith held up between second and third to make sure the ball got through and couldn’t score on the hit.

“You can’t get doubled off to end the game,” Keith said. “So I kind of stopped and made sure it was through. It was a tough read, for sure, but you don’t want to get doubled off to end the game.”

Hinch felt like Keith might’ve gone too far initially anyway.

“It’s a one way or the other read,” he said. “Usually it’s when a ball is that close to being caught, you see the ball through. He was going to be doubled off regardless (if the ball was caught). He got caught in between a little. (Left fielder) Arozarena plays shallow so I don’t know if Colt scores.

“But if you’re going to break, you might as well sellout and get after it. It wasn’t a great day but a learning one in a couple of different ways.

The Tigers (2-4) will open their home schedule Friday against the White Sox.