Oddly enough, Friend is the player to accumulate the most pitching WAR while in a Pirates uniform, but not the pitcher to accumulate the most WAR as a Pirate. Friend was apparently a pretty bad hitter, even for a pitcher, and BR has his total falling from 49.9 as a Pirate to 44.3 once you factor in hitting/fielding. Babe Adams, OTOH, was a better than average hitter for his position, raising his WAR from 45.9 (pitching only) to 47 (everything), making him the leader at the position.

For fun, here’s the highest career WARs of everyone who pitched at least 1/3 of an inning for the Pirates, according to Baseball Gauge (I’m using their metric as I can’t do the same type of search on BR):

Honus Wagner 139.94271
Bert Blyleven 97.06414
Pud Galvin 89.83845
Dazzy Vance 70.95121
Jim Bunning 69.01391
Rube Waddell 67.06919
Luis Tiant 62.49757
Babe Adams 62.38269
Rick Reuschel 61.58766
Jim McCormick 61.40407
Burleigh Grimes 61.28929
Waite Hoyt 59.92822
Guy Hecker 59.09528
Gus Weyhing 56.89412
Adonis Terry 56.3182
Silver King 55.24695
Vic Willis 55.17828
Wilbur Wood 51.09309
Deacon Phillippe 51.05199
Claude Passeau 50.49814
Elmer Smith 48.11098
Wilbur Cooper 47.5008
Bob Friend 47.07174
Ed Morris 46.7126
Jack Chesbro 46.01114
Red Lucas 45.64077
Sam McDowell 45.59184
Pink Hawley 45.20804
Rich Gossage 45.0814

Yes, Wagner is #1. He pitched all of 8 1/3 innings for the team over two years. Heh.

Lot of very good and even great pitchers in that list, but many of them spent very little time with the Pirates. Galvin might be the best pitcher who spent a significant amount of time with the team, by the numbers, but 19th century pitching WARs (particularly pre-1893) are wonky, and I wouldn’t put too much stock in them. Blyleven’s case is well known, and he didn’t spend that much time with the team, but it was still more than the Pirate careers of Vance, Bunning, Waddell, and Tiant (maybe even combined, without looking too closely).

If I was going to pick the greatest Pirates pitcher of all time, it’d probably be… Oh, I dunno, I’ll chicken out and say it’s a toss up between probably Adams, Phillippe, Cooper, and Friend, with I guess Galvin somewhere in that mix too, but he’s very hard to compare to them.

So yeah, some very good guys, but an underwhelming list of candidates for as old as this franchise is.

Of course the greatest pitcher to every pitch for a professional Pittsburgh baseball team would have to be either Smokey Joe Williams or Satchel Paige.