Conversation so far:
What did Albert Spalding play?
Albert Goodwill Spalding was an American pitcher, manager, and executive in the early years of professional baseball.
did Albert Spalding play baseball as a youth?
Having played baseball throughout his youth, Albert Spalding first played competitively with the Rockford Pioneers, a youth team, which he joined in 1865.
What was Albert Spalding's position?
Albert Spalding was primarily a pitcher.
What type of pitching style did Albert Spalding have?
Albert Spalding pitched with his right hand.
did Albert Spalding win any championships?
Albert Spalding was 4-year champion Bostons 1871–75 and manager-pitcher of champion Chicagos in National League's first year.
did Albert Spalding play any other positions besides pitcher?
Albert Spalding also played hitter for the Boston Red Stockings.
who were some of Albert Spalding's team mates?
Some of Albert Spalding's teammates on the Boston Red Stockings were the Wright brothers and Ross Barnes.
what was Albert Spalding's salary as a baseball player?

Question: what was a hallmark of his career?
Self-contained rewrite: what was a hallmark of Albert Spalding's career?