What is the fewest pitches thrown in an inning?

Fewest Pitches Thrown in an InningSix. If the pitchers for the home & visiting teams can induce a ground-out on the 1st pitch to each of the 1st three batters he faces.

I believe it to be 3 (three) if it occurs in the ninth inning for the home team pitcher whose team has a lead, then the inning is complete without the home team having to pitch. Also a putout of any type would suffice, not just a ground-out. Other outs may qualify too, such as batting out of order, however it does not reduce the pitch count. The out of order batter must a have a minimum of 1 pitch.