There is general agreement that on-base percentage is a more effective method than batting average when evaluating a hitter's value.
Most "experts" give much more weight to slugging average than to batting average.
If one accepts the above, then on-base percentage and slugging average against a pitcher must be given great weight when evaluating effectiveness.
Whitey Ford often pitched games in which he allowed seven or eight hits in as many innings, but most of the hits he allowed were singles. At least that's what I remember seeing and Mel Allen telling me.
Baseball-Reference has the data.
In his career, Ford was 236-106 for a .690 winning percentage. He pitched 3,170.1 innings and allowed 2,766 hits, or 7.9 hits per nine innings.
Of the 2,766 hits Ford allowed, 2,078 were singles, 376 doubles, 84 triples and 228 home runs
Batters that faced Ford hit .235 with a .300 on-base percentage and a .340 slugging percentage.
It's simple. How confident is a manager when his batter is a .235 hitter with a .300 on-base percentage and a .340 slugging average? That's why Ford was one of the great pitchers of all time.
Let's take a pitcher that is as important to the New York Yankees today as Ford was to the Yankees during the 1950s and early 1960s.
CC Sabathia has pitched for the Yankees since 2009. In his three full seasons with the team, he has worked 705 innings, allowing 636 hits or 8.7 hits per nine innings. Ford's numbers were a little better in this area.
Of the 636 hits Sabathia has allowed, 450 were singles, 120 were doubles, 11 were triples and 55 cleared the fences.
Batters that faced Sabathia hit .242 with a .299 on-base percentage and a .359 slugging average. Excellent numbers, but a little short of Ford.
This is not a comparison between Ford and Sabathia. Their statistics have been used only to illustrate the importance of emphasizing these three measurements when evaluating a pitcher.
I am curious, so let's research one more Yankee.
Mariano Rivera has pitched 1,219.2 innings, allowing 940 hits, or 6.9 hits per nine innings. That is incredible.
Of the 940 hits Rivera has given up, 729 were singles, 131 were doubles, 15 were triples and 65 were home runs.
Rivera's batting average against was .210, his on-base percentage against was .262 and batters "slugged" .290 against him.
As Red Barber might ask Phil Rizzuto, "Phil, do you think Rivera was a pretty good pitcher?"