Stanton hit a two-run shot just to the right of straightaway center with two outs in the fifth that ended Harvey's outing Saturday as the Yankees beat the Mets 10-3.
''One too many fastballs,'' Harvey said. ''That one, obviously, ran back over the middle of the plate. A hitter like that, you can't do that.''
The drive ended Stanton's spring-training opening 20 at-bat homerless drought. He does have seven hits in 21 at-bats (.333) overall for the NL MVP who led the majors with 59 home runs last year.
''Just a good adjustment from the second at-bat ... don't miss the fastball away,'' a smiling Stanton said.
Harvey went 4 2/3 innings, giving up five runs, six hits, one walk and striking out two.
''A lineup like that, you really have to be fine,'' Harvey said. ''I think it's tough to say March 10 you're going to be as fine as you want to be. But overall mechanically, it was great. Everything feels awesome. I'm really excited about that.''
Harvey's lone walk proved costly, coming to Aaron Judge one batter before Stanton's longball.
''Needed ear plugs at first base,'' Judge said. ''A thing of beauty.''
Harvey hit Stanton with a pitch on the right forearm during a two-run first, but struck out the slugger in the third.
Judge and Brett Gardner both had two hits off Harvey,
Harvey was coming off a start Monday against Detroit where he allowed two hits over three scoreless innings in his second spring training appearance.
An All-Star who started the 2013 game at the Mets' Citi Field, Harvey has struggled since tearing the ulnar collateral ligament in his pitching elbow that August. He was 13-8 with a 2.71 ERA over 29 starts when he returned in 2015 following Tommy John surgery, then slumped to 4-10 with a 4.86 ERA n 2016, when he didn't start after July 4 because of Thoracic Outlet Syndrome, which required another operation.
He wound up 5-7 with a 6.70 ERA last year, when he was sidelined from mid-June until September because of a stress fracture in his scapula, which connects the arm with the collarbone.
Harvey is eligible for free agency after this season.
NOTES: Yankees starting 2B candidate Tyler Wade said he was OK after rolling his left wrist diving for Jose Reyes' infield single in the sixth. ''Scary more than anything else,'' Wade said. ... Mets SS Amed Rosario played three innings of defense. He hadn't been in the field for a week due to a groin injury. ... Mets DH Tim Tebow went 0 for 3 with two strikeouts and he walked once. He is hitting .071 (1 for 14). ... Stanton hit a hard foul straight back in the first that cracked a press box window.
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