Brewers beat Cubs 4-3 in 10 innings
The former Japanese batting champion entered the game with one homer, an inside-the-park homer on April 20.
Aoki was mobbed by his teammates at home plate.
Corey Hart hit a game-tying RBI double in the eighth for the Brewers, who took two out of three games from their NL Central rivals.
Bryan LaHair temporarily gave Chicago the lead with a pinch-hit home run in the eighth and Koyie Hill added an RBI double for the Cubs. Coleman (0-1) took the loss.
John Axford (1-2) earned the win.
Brewers starter Randy Wolf gave up four hits and two walks, striking out six.
Cubs starter Matt Garza went six innings, giving up three hits and two runs with a walk and six strikeouts.
With the Cubs trailing 2-1 and two outs in the eighth, Alfonso Soriano singled. LaHair then pinch hit for Jeff Baker, and pounded a pitch from Francisco Rodriguez deep to right-center field to give the Cubs a 3-2 lead. It was LaHair's second career pinch-hit home run.
Aoki legged out an infield hit to start the bottom of the eighth, then went to second on a sacrifice bunt by Carlos Gomez.
Ryan Braun flew out, but Hart doubled to tie the game.
Aramis Ramirez, who has been out since Saturday with a left quadriceps strain, appeared as a pinch hitter but was walked intentionally. Pitcher Zack Greinke pinch ran for Ramirez but didn't go anywhere, as Rickie Weeks struck out to end the inning.
Garza didn't allow a hit until the fourth, when Aoki led off and hit a 1-1 pitch over the wall in right field to give Milwaukee a 1-0 lead.
Aoki's solo shot in the fourth inning was his second home run this season -- but the first one that actually left the ballpark.
The Brewers had another chance in the fifth after Weeks reached base on a fielding error by first baseman Jeff Baker, Garza walked Cody Ransom, and Edwin Maysonet sacrificed the runners to second and third. But Wolf hit a sharp liner that was caught by second baseman Darwin Barney, and Aoki grounded out to end the inning.
Milwaukee added another run in the sixth, when Corey Hart hit a two-out double and Kottaras drove him in with a single to put the Brewers up 2-0.
The Cubs had a chance in the seventh when Baker led off with a walk and Joe Mather reached base on a fielding error by third baseman Ransom.
Wolf got Ian Stewart to hit into a double play, but Hill hit an RBI double to cut the Brewers' lead to 2-1.
Notes: Ryan Braun had a rare moment of frustration at the plate in the first inning. After lunging at a pitch to strike out and end the inning, Braun tossed his bat high in the air and slammed his helmet on the ground. ... A play originally ruled an error on Stewart later was changed to a base hit by Braun. ... Ransom's error broke a nine-game errorless streak for the Brewers.