Miami has won four straight, and seven of its last nine.
Yelich has heated up in the second half, with four home runs and 12 RBIs since the All-Star break.
With Stanton, tied for the Major League lead with 33 home runs, having a big month with 12 long balls, the Reds have been working around the slugger to get to Yelich.
"I don't blame them," Yelich said. "[Stanton] has 30-something homers and has been red hot lately, hitting everything out of the park. It makes sense. Teams are going to be careful with him. You make a mistake to the big fella, it's going a long, long way."
Yelich, now with 12 home runs and 55 RBIs, showed some power of his own, going to the opposite field on an 0-2 Tim Adleman offering. Statcast™ projected the distance of the homer at 403 feet with an exit speed of 103.5 mph.
"That was huge because we're down a run," Marlins manager Don Mattingly said. "We hit some balls hard, so you're feeling good about it. We hit some balls at people, so you feel like you're going to have some hits in there and have a chance to score some runs. … I thought Yeli's homer was probably the biggest hit of the game there just because it puts us back on top."
Added Stanton: "That was good. It was 0-2. You leave a pitch like that, usually with two strikes, Yeli sprays it. It was elevated enough to do damage with it."
Yelich certainly has the ability to change the game with one swing, but what was eye-opening about his three-run drive was it went to left-center, just his second opposite-field home run this year at Marlins Park.
Both have actually come since the break. He sent a pitch to a similar location on July 19 against Phillies right-hander Nick Pivetta. Statcast™ projected that homer, off a 93.3-mph fastball, at 405 feet with an exit speed of 104.8 mph.
"That's No. 2 in five years," Yelich noted about going the opposite way at home. "I don't know, man. I'll take them. You've got to earn them. You don't really get any cheap homers in this place."