Both these beleaguered starters have ERAs over seven, and plenty of offense could be the result Sunday as the Giants seek a three-game home sweep.
Vogelsong (0-1, 7.71 ERA) allowed five runs over 1 1-3 innings Monday in an 8-2 loss at Colorado, surrendering three homers to the 13 batters he faced.
"I'm definitely not happy about it," Vogelsong said. "It's embarrassing really."
The right-hander's only shorter start came when he failed to retire all seven Cincinnati batters he faced in a 2004 loss for Pittsburgh.
Vogelsong is 1-3 with a 6.61 ERA over his last 10 starts. Left-handed hitters are batting .389 against him this year for one of baseball's highest marks.
Salazar (0-3, 7.85), meanwhile, is also enduring some major struggles. He has failed to last past the fifth inning in losing three straight outings, allowing five runs in 4 1-3 in Tuesday's 8-2 defeat to Kansas City.
The Indians (11-13) had high hopes for the right-hander, who posted a 3.12 ERA in 10 starts a year ago and also took the ball in their wild-card loss to Tampa Bay.
"It's a short sample size," manager Terry Francona told the Indians' official website. "We can't forget last year when he was pitching, he was on a pretty strict limit for health reasons. So now he's starting to get stretched out a little bit. It's been a while since he's done that. He's never done it at the major-league level, so sometimes you have to be patient."
San Francisco (14-10) is no doubt hoping that struggling Buster Posey can take advantage of the inexperienced Salazar. Posey homered in Saturday's 5-3 victory, although he remains in a 4-for-39 slide.
''I was happy for Buster,'' manager Bruce Bochy said. ''You go through these tough streaks and it's not easy.''
The Giants have been getting production from Michael Morse, who is 4 for 9 with three homers in his last three games. Hunter Pence is 10 for 20 in his last five games, going 3 for 8 with four RBIs in this series.
The Indians blew a 3-0 lead in the fifth inning Saturday, as the Giants scored four times in that frame highlighted by Pence's two-run single.
''That one inning, it just got contagious,'' Bochy said.
Cleveland leadoff hitter Michael Bourn is 10 for 27 during a six-game hitting streak, including 3 for 9 with three runs scored in this series. No. 2 hitter Nick Swisher is 4 for 9 in the series with two doubles and No. 3 hitter Jason Kipnis is 3 for 9 with two RBIs.
It's the next three batters that have let down Cleveland, going 19 hitless at-bats. Francona may want to shuffle things after using Carlos Santana, Michael Brantley and Asdrubal Cabrera in those slots in the first two games.