The most successful non-pitchers on the mound

Question

A couple of seasons ago, Baltimore's Chris ("Crush") Davis filled in as an emergency pitcher in a long, extra-inning game, pitching 2 innings and not giving up a run. What non-pitcher has the best ERA with more than 5 innings for a career?

Answer 1

Thanks to SamtheBrand for the great chart showing how non-pitchers faired statistically on the mound. Some would doubt the inclusion of Babe Ruth to the list because most of his incredible pitching statistics were done when he was principally a pitcher for the Red Sox. Many of the other "non-pitchers" with substantial stats as pitchers played 100 years ago. But of those from the "modern" era of baseball, one name stands out -- Jimmy Foxx. The Hall of Fame 3B and Catcher offered to pitch when needed for the Phillies in his last season, 1945, when his hitting had gone sour because of declining eye sight. Still, the war was still going on, and the player pool was thin.

One biographer captured that year:

Foxx hit the last seven home runs of his career for the Phillies, but what made his final season unique was his turn on the pitching mound. Volunteering to help the team out in any way he could, Foxx pitched 23 innings, with a 1-0 record and 1.59 ERA. His high point on the mound came in the second game of a doubleheader on August 19, when Foxx pitched five no-hit innings in an emergency start. (He had pitched once very briefly while with the 1939 Red Sox.) His last major-league at-bat came against the Dodgers on September 23. At the close of the season Foxx retired for good, with a .325 lifetime batting average, 2,646 hits, and 534 home runs—a total that was second only to Ruth until 1966. His total of 1,922 runs batted in still ranked as 8th all time in 2008.

Source: http://sabr.org/bioproj/person/e34a045d