Joe Kelly (0-2) allowed runs for the first time in five appearances and took the loss. He allowed two hits and a walk in one inning for the Cardinals, who fell to 0-3 in extra-inning games.
Jim Henderson worked a perfect inning for his eighth save in eight chances.
Bianchi made his second start since coming off the disabled list on May 2 after he sidelined by bursitis in his left hip. The winning hit gave him his first two RBIs this season.
The Cardinals used four consecutive singles with two outs in the sixth inning to tie it 4-4. Matt Carpenter's hit chased Milwaukee starter Marco Estrada and drove in Pete Kozma who started the rally. Jon Jay's single brought in Ty Wigginton.
Braun gave Milwaukee a 4-2 lead in the fifth with his second single of the game.
The Brewers broke through in the third with a two-out rally. Segura's fourth triple of the season drove in Bianchi and Norichika Aoki to make it 2-2. Braun gave Milwaukee a 3-2 lead with his first single.
St. Louis scored twice in the second but left the bases loaded. Kozma drove in Allen Craig, who walked to start the inning. Carpenter's single gave the Cardinals a 2-0 lead.
Estrada gave up four runs, seven hits and four walks over 5 2-3 innings. He struck out two.
Lance Lynn lasted just five innings. He gave up four earned runs on eight hits and two walks as his ERA rose to 3.27 from 2.88.
He struck out three, his fewest since his first start of the season when he was lifted after four innings at Arizona on April 3.
NOTES: Brewers LHP Chris Naverson threw curveballs Friday for the first time since going on the 15-day disabled list April 7 with a strained left middle finger. Milwaukee manager Ron Roenicke said it was the final test before he was cleared to throw in a rehab game. . Milwaukee LHP Tom Gorzelanny remains on pace to return from the disabled list at the end of the month. He is set to throw a bullpen session Sunday and a simulated game Tuesday. He has been sidelined because of tendinitis in his left shoulder on May 8. . Former Cardinals OF So Taguchi provided color commentary on the game for Japanese broadcaster NHK from its Tokyo studio.
Link to box score: Milwaukee 6 at St. Louis 4 (10 innings)
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