Adam LaRoche, Miguel Montero, Mark Reynolds and Stephen Drew all went deep with one out during the four-run frame. The homers came in a span of 10 pitches as Bush became the third big league pitcher to allow four consecutive homers.
The others are Chase Wright of the New York Yankees in the third inning against Boston on April 22, 2007, and Paul Foytack of the Los Angeles Angels on July 31, 1963, in the sixth inning of the second game of a doubleheader against Cleveland.
Bush also tied a major league record for most homers allowed in an inning.
Daniel Hudson (3-0) had a career-high nine strikeouts over seven innings. and won his third straight start since being traded from the White Sox last month. The right-hander, who allowed seven hits and two runs, added a three- run double in the sixth inning.
Bush (5-10) was tagged for eight hits and seven runs over 5 1/3 innings, losing for the fourth time in his last five decisions.
LaRoche homered to right field on a 3-2 pitch with one out in the fourth. Montero belted a ball to the second deck in right field and then Reynolds connected off the facing of the second deck in left-center. Drew was next and he lined a 1-0 offering over the wall in right to give Arizona a 4-2 lead.
Before Wednesday, Bush hadn't allowed a homer in three straight games.
It's the seventh time in major league history a team has hit four consecutive home runs in the same inning. The four straight HRs are the first time it's occurred in Arizona history.
Bush walked Montero and Drew in the sixth before hitting Gerardo Parra with a pitch. Todd Coffey entered with one out, but Hudson doubled to center to clear the bases. After two more walks, Justin Upton's fielder's choice plated Hudson for the game's final run.
Milwaukee had its chances to come back. It put men on second and third with one out in the seventh, but couldn't capitalize. It loaded the bases the following frame, but Jordan Norberto fanned pinch-hitter Ryan Braun to end the inning.
Parra's single in the third inning snapped an 0-for-19 hitless streak...The Drew brothers (J.D. and Stephen) have been involved in three of the seven times a team has hit 4 consecutive homers...The Diamondbacks became the third NL team to hit four straight homers in a game, joining the Dodgers on Sep. 18, 2006 and Braves on June 8, 1961...Fielder played in his 300th consecutive game.