SEATTLE -- For Daniel Norris, it’s the finishing touches that remain an individual hurdle.

On Friday night, Norris threw six shutout innings against the Mariners on 89 pitches, retiring 15 of 16 entering the seventh while showing sharp command of his secondary pitches, particularly his changeup, which had been marginally successful. His efficiency, which has been a problem at times, was not an issue, as Norris tied a season-high with 100 pitches.

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Norris was ultimately plagued by a lack of run support, and the Tigers were walked off in a 3-2 loss in the bottom of the ninth when Seattle’s Mallex Smith roped a single to center off Jose Cisnero with runners on second and third and two outs.

The loss spoiled what was shaping up to be arguably Norris’ best start of the season. In the seventh, it only took a mistake changeup left up that Daniel Vogelbach turned into a double and a well-placed slider dipping below the zone that Tom Murphy dug out and turned into a two-run homer to erase a two-run lead, as Norris was seeking his first win since May 12.

“I feel like I lost it for us. I've got to finish strong and finish what I started,” Norris said. “I feel like it wasn't a terrible pitch [to Murphy], but I've got to throw something different there, I guess. … I felt good. Obviously, I wanted the ball [in the seventh]. I've just got to finish my start. I'll let it linger for 10 more minutes, then look forward to my workout tomorrow and getting back after it.”

Norris, who has lost more than three mph of average fastball velocity since 2016, and as such has turned more to his offspeed. Of his eight strikeouts, he racked up five on his changeup and two on his slider. He did so on a night that he didn’t entirely trust his curveball.

Entering Friday, opposing hitters were batting .282 against his changeup, which was the 13th-highest among 85 pitchers who’ve had at least 50 at-bats decided on the offering.

“The changeup he threw kind of surprised us,” Mariners manager Scott Servais said. “He’d been throwing a lot of sliders and we heard he had a decent changeup. But it really had bottom to it. We chased a lot of them out of the zone. It wasn’t your typical changeup at 81-82 mph. It was harder and had a lot of movement to it. That was really a key pitch for him tonight. Something we had not seen a lot of from him on video or the scouting reports.”

Norris has weathered a topsy-turvy season to the tune of a 4.89 ERA and 16 Tigers losses over his 21 starts, and he’s given up five earned runs or more in five of those outings. But for a pitcher whose 90.7 average exit velocity against and 43.9 percent hard-hit rate both rank in the bottom seven percent of the league, the 12 swinging strikes he generated and ability to locate low in the zone were encouraging signs in the eyes of the Tigers.

“He's been good plenty of times,” Tigers manager Ron Gardenhire said. “The big thing with Danny is his pitch count normally gets high really quick early in the game. Today, he was fine. He was cruising. ... Everything was good. He had his pitches and he was making good use of him. Unfortunately, they got him in the seventh.”

Norris has received just 55 runs of support this season (2.6 per game), and the solo home runs from first baseman Brandon Dixon and catcher John Hicks ultimately weren’t enough.

A baserunning miscue by third baseman Jeimer Candelario in the fifth erased what would’ve been Detroit’s third run, which manifested when Candelario was doubled up off second base while surging to third on a lineout by Hicks with no outs. Jordy Mercer went on to single, which likely would have allowed Candelario to score.

“That's just a bad baserunning play. He made a mistake,” Gardenhire said. “Any time there's a line drive with no outs, you have to freeze on it. You have to check the ball. He just took off running. He thought it was a base hit. You can't think in that situation. You've got to recognize it and look back and see.”

The loss was the Tigers’ 26th in their past 30 games, dropping their MLB-worst record to 30-69. They have just one win in their past 23 games against the American League West, a division that will feature each of their opponents on their current 11-game road trip.