Webster McDonald was a right-handed "submarine artist" that pitched for a number of great Negro League teams including the Chicago American Giants, the Homestead Grays and the Philadelphia Stars. In 1952, the Pittsburgh Courier voted him to their "Honor Roll" team as one of the best African American pitchers of all time.
This photo, which was published in the Philadelphia Daily News around the time of his death in 1982, appears to show McDonald warming up for Gilkerson's Union Giants sometime in the late 1920's.
McDonald only pitched for Gilkerson a handful of times in 1928 and 1929. He was never a regular member of the Union Giants' roster. Instead, Gilkerson would hire him on a limited basis for big games at the end of the season, especially tournaments with large purses.
Between 1928 and 1931, McDonald pitched for a white team in Little Falls, Minnesota for most of the season. The Union Giants traveled in that part of the country often, playing the Little Falls team a number of times during those years. In late August 1928, the Union Giants faced off against McDonald. He struck out seven of the Union Giants in a extra inning game, but had no run support whatsoever. The Union Giants beat the Little Falls team, 1-0, in 12 innings. Less than a month later, McDonald was pitching for the Union Giants in Iowa.
In June 1929, McDonald threw a shutout against the Union Giants in Little Falls, allowing just five singles in the game. Three months later he was back on the mound for Gilkerson's team pitching in the championship game of the Eastern Nebraska tournament at Arlington. McDonald and the Union Giants went up against a team from Blair, Nebraska that was made up of mostly Western League players.
"McDonald, former American Giants Hurler Holds Opponents in Palm of Hand," proclaimed the Kansas City Call. He gave up just one run on six hits. The Union Giants won the championship easily, 10-1, which came with a $1,000 prize.
McDonald briefly remained with he Union Giants, pitching again is Sioux City a few days later. Against the local Stockyards team, McDonald started the game but only pitched three innings, giving up three hits and two runs. This was likely the last time McDonald pitched for Gilkerson... or was it?
Starting in 1928, Gilkerson had a mysterious "submarine twirler" that would occasionally pitch for him, typically in Canada. He was only ever listed as Duff. The Winnipeg Tribune claimed he was "rated as the best colored submarine pitcher in baseball." In mid-July 1928, Duff pitched part of a game against the House of David team in Winnipeg. "Duff's peculiar delivery and his underhand ball which broke sharply, had the bearded stars swinging wildly in the two rounds that he worked. He was nicked for a single hit, while he whiffed four," wrote the local paper. The very next night Duff pitched again. This time a complete game against the House of David, giving up only one run on five hits. The Union Giants won, 2-1.
When the Union Giants returned to Winnipeg in August, Duff was back with the team, at least for one game. He showed up to pitch against the Plentywood, Montana team which featured six former major league players, including Happy Felsch. Thanks to Duff, the Union Giants were able to beat the Plentywood club that night. It would be their only win in a four game series with the all-star team. The Winnipeg Tribune reported, "Duff was in his element last night. His usual control was perfect and he displayed to the fans once again his ability to cut the plate in half at any time he chose to do it. He didn't walk a man and made eleven Plentywood batters bite the dust. His submarine ball looked tantalizingly easy to hit, yet the batters couldn't connect." After one game, the dominant pitcher disappeared as quickly as he came.
The name Duff wasn't associated with the Union Giants again until late in the 1930 season. The Union Giants provided a possible lineup for the Southwestern Iowa tournament and it included a pitcher named Duff. There is no evidence however that Duff ever pitched in any of the contests. The Union Giants lost the tournament's championship game to the Kari-Keens of Sioux City. Duff however did return briefly the next year. In early June 1931, he pitched at least one game against the Stockyards team of Sioux City and then was gone for good.
So who was Duff? The most logical answer is that it was Webster McDonald pitching under an assumed name. But why? McDonald told John Holway in a 1970 interview that his top salary with the Little Falls team was $750 a month with expenses and transportation included, making him the highest paid player in the league by a long shot. With that in mind, it is quite possible he used an alias so as to not jeopardize his contract with the Little Falls team. This is only a theory however and needs more research.
Additional Notes:
Gilkerson had another pitcher named McDonald in 1933 and 1934 however this could not have been Webster as he was playing and managing in Philadelphia by then. Instead, it may have been Luther McDonald.
For more info on Webster McDonald please see his SABR bio by Leslie Heaphy.


