Berrios (1-0), one of the Twins' first-round picks in this year's Draft, struck out seven, walked one and allowed just one hit -- a two-out double to left by Carlos Franco in the first inning.
The 18-year-old escaped his worst threat an inning later when he walked Aris Alcantara and beaned Edison Sanchez, but Blake Brown bounced into a double play and Berrios caught Ronald Luna looking for the third out.
Beginning with the double play, Berrios retired 15 straight before handing the ball over to Tyler Duffey, who whiffed four over two perfect innings. J.T. Chargois surrendered the Braves' second hit in a scoreless ninth to finish off the win.
For Berrios, the No. 32 pick in the Draft out of Papa Juan XXIII High School in Puerto Rico, the win comes in only his fourth Appy League start. The right-hander went 2-0 with a 1.29 ERA in three starts for the Twins after appearing in eight games (one start) for Minnesota's Gulf Coast League affiliate earlier this summer.
In 30 2/3 regular seasons innings, the Bayamon, Puerto Rico native struck out 49 batters and walked just four.
Walker, who went 3-for-4, crushed a two-run shot in the second after D.J. Hicks reached on a leadoff double. The right fielder doubled and scored in the sixth and then singled and stole second in the eighth.
Byron Buxton, the Twins' No. 1 pick in the Draft, went 1-for-3 with an RBI.
In other Appy League action:
Johnson City 2, Burlington 1
Cardinals starter Silfredo Garcia struck out six and held the Royals to a pair of hits over six frames and Carson Kelly homered to help Johnson City take a 1-0 lead in its semifinals series.
Kelly led off the fourth with a homer off Burlington starter Christian Binford, and Johnson City took a 2-0 lead in the seventh on Jeremy Schaffer's RBI single. Humberto Arteaga scored the Royals' lone run in the eighth on a fielder's choice and an error -- Terrance Gore was thrown out at the plate on the play, keeping the Cards ahead.
Binford struck out six, but allowed a run on three hits to suffer the loss. Box score.