3 assists by an OF has happened 44 times? I can't even remember it ever happening once (in my 38 years of following baseball)
Sorry about that -- the four-stikeout inning occurred 44 times. I have no idea how many three-assist innings there are in major league history. Now that I think about it, even a two-assist inning (for an outfielder) must be quite a rarity.
I remember Reggie Jackson doing this once in the late 1970s. Two identical plays right after each other. One guy grounded a single to right field with a runner on second, and the runner was thrown out at the plate. The batter took second base on the throw. The next batter grounds a single to left field, and the runner on second was thrown out at the plate!
I would say that the rarest of the rare is the unassisted triple play. I'd have to look it up, but I think there have been more perfect games pitched than unassisted triple plays.