Yovani Gallardo has his eye on March 31 and the second opening day start of his career.
"It felt good out there," Gallardo said. "I was falling behind some of the hitters in the first inning, but felt better after that and my fastball was coming out of my hand the way it did in my last start.
Shaun Marcum will pitch the Brewers' second game at Cincinnati on April 2. He was supposed to start Thursday, but was pushed back to Saturday against Arizona to get on the proper schedule.
Milwaukee tied it at 1 in the fifth on Erick Almonte's triple, and took a 3-1 lead in the sixth on a single by Mike Rivera and a wild pitch.
The Athletics tied it at 3 with two runs in the top of the eighth. Josh Whitaker hit a run-scoring double for the first run and Matt Carson's single tied the game at 3.
In the bottom of the eighth, Boggs' third hit of the game scored Chris Dickerson, who led off the inning with a pinch-hit single.
Oakland starter Tyson Ross pitched three scoreless innings, allowing four hits while walking two and striking out one.
Notes: Brewers reliever Takashi Saito left the club temporarily on Friday. He located his wife and two daughters in Japan following the earthquake there and they were OK, but had trouble reaching his parents. They were located later in the day. ... Milwaukee 2B Rickie Weeks was removed from the game early for the second straight day due to tightness in his groin. Manager Ron Roenicke said it is nothing serious but is being done as a precaution. Weeks played against his younger brother, Jemile, a non-roster infielder with Oakland.