The Padres moved Fernando Tatis Jr. out of the leadoff spot for the first time all season and into the third spot in the batting order Saturday night against the D-backs in an effort to generate more offense.

They penciled him in as the designated hitter to get him off of his feet and give him a “half day” off.

It took three pitches to remind everyone that Tatis does not take days off.

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In the first inning at Chase Field, the Padres’ star smashed the third pitch he saw from D-backs left-hander Alex Young into the stands above left field for his ninth home run of the season. Tatis also had a two-run double in a ninth-inning rally, but the Padres fell, 7-6, for their fourth straight loss.

Against Young, Tatis connected on a 91 mph sinker on a 2-0 count -- his first swing as a DH in the Majors -- and produced a 111.8 mph exit velocity on the 410-foot shot, per Statcast.

The homer put his team ahead, 1-0, and tied him with Yankees slugger Aaron Judge for the Major League lead. Angels star Mike Trout also hit his ninth home run of the season Saturday night.

In the ninth, Tatis’ double cut Arizona’s lead to two runs. He then scored on a single by Greg Garcia to get the Padres within a run, 7-6.

For the second time in 10 days, the Padres saw a late rally thwarted when the final out was recorded at home plate. Last week against the Dodgers, Trent Grisham was thrown out after a flyout. On Saturday, Jorge Mateo was cut down trying to score from first on a single to center field by Jurickson Profar.

D-backs center fielder Starling Marte threw to second baseman Ketel Marte, who made the relay home, where catcher Carson Kelly applied a game-ending tag. Actually, the game didn't end until after a replay challenge from Padres manager Jayce Tingler.

“He was running on the play,” Tingler said. “Profar got the hit, and we chose to send him. We thought his hand may have gotten in and we had them review the entire play to make sure he had a lane and if his hand got in there. We asked New York to review the entire play.”

As for Tatis, if he ends up alone atop the Major League home run leaderboard, he would join Eddie Mathews (1953) and Sam Crawford (1901) as the only players in the Modern Era (since 1900) to do so in their age-21 seasons. No one has led the Majors in home runs at a younger age.

Tatis wasn’t the only Padres star Saturday. Starter Cal Quantrill was solid on the mound in his bid to join the rotation. The 25-year-old right-hander was charged with one run on three hits in 3 2 /3 innings before yielding to Matt Strahm, who allowed one hit in 1 1/3 innings.

“I can see from the outside how it would appear that we were all auditioning,” Quantrill said. “Right now, we're trying to find ways to win ballgames, and it was my turn to try it. … I'm a player. I'll let the coaches make the coaching decisions.”

The D-backs built a 7-1 lead before the Padres stormed back with two runs in the eighth inning and three in the ninth. Then came that final play at the plate.

“I was really happy to see the guys fight to the very end and make it down to an inch or two in the very end,” Tingler said. “It took a really good throw to do it and Mateo was busting it from the get-go. He got around there quick, and I thought it was a good roll of the dice.”