Julio Teheran appears more than capable of keeping the clamps on the Giants' lineup, but perhaps Wednesday's matchup will help San Francisco get back on track after taking him deep three times earlier this month.The Braves (22-16) ended a five-game road losing streak with a 5-0 victory Tuesday, matching their run total from the four losses they had previously suffered in the season series. Mike Minor gave up three hits in 6 2/3 innings, lowering Atlanta's already major league-best starters' ERA to 2.53.Teheran (2-2, 1.71 ERA) has been perhaps the most impressive member of the rotation, posting a sparkling 0.81 WHIP. However, he owns a run-support average of 2.64 and has received a total of six runs of support over his last five starts spanning 39 innings.He's 2-1 with a 2.70 ERA in three starts versus San Francisco (25-15), but gave up three runs on solo homers to Buster Posey, Michael Morse and Brandon Belt over seven innings of a 3-1 loss at home on May 3. Posey is 6 for 9 against him with another homer while Belt is 5 for 9.Teheran has served up only four homers over 51 innings in his seven other starts.He bounced back in strong fashion Friday against the Cubs, yielding only a Mike Olt homer in eight innings while striking out a season-high nine."I felt great," Teheran told the team's official website. "I was mixing my pitches a little better today. Everything was working pretty well today."The Giants had won four of five and 14 of 18 but were 0 for 7 with runners in scoring position Tuesday. Buster Posey was 0 for 4, going hitless for just the third time in 15 games and failed to make a tag on Jason Heyward in the sixth despite a throw that easily beat him to the plate, allowing Heyward to score the first of three runs in the inning."I thought I was in the right position," said Posey, whose hitless night was also just his second in his last 18 matchups with Atlanta. "I didn't think there was a way for him to get around me."San Francisco might not need much offense Wednesday with Madison Bumgarner (4-3, 2.83) coming off back-to-back wins in which he allowed an earned run over 14 innings.However, both were on the road, where he owns a 1.39 ERA in five outings compared to a 5.87 mark in three starts at AT&T Park. Bumgarner has issued nine walks in 15 1/3 innings at home compared to just six free passes in 32 1/3 innings on the road. He entered the season with a 2.89 career ERA at home.Bumgarner is 3-3 with a 2.51 ERA in seven starts versus Atlanta, including a 0.45 mark in the last three. He gave up an unearned run and three hits over six innings in a 4-1 road victory on May 4.Justin Upton is 9 for 23 against him.