[Mick]

Three Giants have pitched an immaculate inning (3 strike-outs on nine pitches).  Who were they?

BC

Wallender was correct with Hershiser.  The other two were:

Trevor Wilson, on June 7th 1992 against the Houston Astros, striking out Jeff Bagwell, Eric Anthony, and Rafael Ramirez on 9 pitches in the 9th inning.
Santiago Casilla, three years ago (May 17, 2015) against the Cincinnati Reds, striking out Marion Byrd, Brandon Phillips, and Jay Bruce on 9 pitches in the 9th inning.

Crazily enough, in 1979, the Giants were the victims of three immaculate innings.  Ouch.

BC

There were only three immaculate innings thrown in 1979, and the Giants had all three. 

The Giants have had only one other immaculate  inning in their history, four years ago against Rex Brothers of the Colorado Rockies.  He mowed down the Giants #5, #6 and #7 hitters that day, Michael Morse, Brandon Crawford and Gregor Blanco.  Brothers' ERA at the time was 4.85 and was 5.59 by year's end. It was his worst record in his eight year (to date) career.  He wasn't a great pitcher, but Morse struck out 121 times that year, Crawford struck out 129 and Blanco struck out 77 times.

Now for the trivia.  Four pitchers have thrown multiple immaculate innings.  Only one has thrown three.  Name that pitcher.

[Mick]

Three Giants have pitched an immaculate inning (3 strike-outs on nine pitches).  Who were they?

BC

Wallender was correct with Hershiser.  The other two were:

Trevor Wilson, on June 7th 1992 against the Houston Astros, striking out Jeff Bagwell, Eric Anthony, and Rafael Ramirez on 9 pitches in the 9th inning.
Santiago Casilla, three years ago (May 17, 2015) against the Cincinnati Reds, striking out Marion Byrd, Brandon Phillips, and Jay Bruce on 9 pitches in the 9th inning.

Crazily enough, in 1979, the Giants were the victims of three immaculate innings.  Ouch.

BC

There were only three immaculate innings thrown in 1979, and the Giants had all three. 

The Giants have had only one other immaculate  inning in their history, four years ago against Rex Brothers of the Colorado Rockies.  He mowed down the Giants #5, #6 and #7 hitters that day, Michael Morse, Brandon Crawford and Gregor Blanco.  Brothers' ERA at the time was 4.85 and was 5.59 by year's end. It was his worst record in his eight year (to date) career.  He wasn't a great pitcher, but Morse struck out 121 times that year, Crawford struck out 129 and Blanco struck out 77 times.

Now for the trivia.  Four pitchers have thrown multiple immaculate innings.  Only one has thrown three.  Name that pitcher.