AL teams have the DH, so their rosters will have fewer pitchers than the NL, right? NL teams have more temptation to pinch-hit for pitchers, so they need more relievers on the roster, right?

As of May 1st, the average NL roster has 12.3 pitchers, while the average AL roster has 11.9. So, the average NL roster has 0.4 of a pitcher more. Simple histograms appear below.

14 NNNNN 13 AA NNNNNNNNNN 12 AAAAAAAAAAA 11 A 10 A 09

BTW, it’s the Angels who have only ten pitchers.

Small sample size. Maybe I’ll gather more data later in the season.