The All-Star outfielder also plated three RBIs and scored two runs in the extra-innings affair on Wednesday at Great American Ball Park.
"I've never seen a game like that. It was incredible," Brewers manager Craig Counsell told reporters. "He's coming up there and you're thinking he can't do it again, and he does it again. Then he makes a great throw to keep that inning at zero. He did everything tonight, he really did. He's driving the bus home tonight."
Yelich began his hitting spree with a single in the top of the first inning.
He singled again in the top of the third inning, before smashing his 26th home run of the year in the top of the fifth inning. That two-run shot plated teammate Lorenzo Cain and gave the Brewers a 4-3 lead. That ball traveled 398 feet and had an exit velocity of 108 mph, according to Statcast.
Yelich got even closer to the cycle with a sixth-inning double. He completed the rare feat in the next inning. The Brewers star was facing Reds reliever David Hernandez during that exchange. Hernandez dropped in a 1-0 changeup, which Yelich sent on a line drive to right field. He hustled to third base and plated Cain again for an RBI, tying the game at 10-10.
But Yelich wasn't finished. The Brewers outfielder got his third single of the game in the top of the ninth frame. Milwaukee pulled ahead for good in the National League Central clash with a leadoff homer from Jesus Aguilar in the top of the tenth inning.
Yelich is now hitting .319 with 26 home runs and 75 RBIs in his first season with the Brewers. He joined the team this offseason in a trade from the Miami Marlins.
The Reds won the first game of the three-game series on Tuesday in Cincinnati. The series finale is set for 12:35 p.m. on Thursday at Great American Ball Park.