McKnight's career in baseball began in 1876, when he and several local organizers formed the Allegheny Base Ball Club. The founding occurred just twenty days after Pittsburgh lost its bid to join the newly-formed National League. The club was named Pittsburgh Allegheny, a minor league baseball club which is unaffiliated with the modern dayPittsburgh Pirates. The team played their first game at Union Park on April 15, 1876, defeating the Xanthas 7-3, at Union Park. In 1877, McKnight was named the manager of the Pittsburgh Allegheny as the club became one of the first minor league baseball clubs as member of the International Association for Professional Base Ball Players. He also later served as the International Association's president after Candy Cummings resigned from the post. The team and the league would however fold in 1878.
On November 2, 1881, McKnight served as Allegheny's representative at the Gibson House in Cincinnati, Ohio during the founding meeting of the American Association. At the meeting, McKnight was made temporary chairman and Jimmy Williams was chosen temporary secretary of the Association. McKnight was the principal owner of the Pittsburgh Alleghenys in the American Association and even served as the club's manager at the beginning of their 1884 season. In 1884, Edmund C. Converse, of the National Tube Company, succeeded McKnight as president of the club, which remained in the American Association for the next five years.
Move to the National League
McKnight served as president of the American Association until he was ousted in. His ouster was result of a controversy surrounding St. Louis Browns player Sam Barkley. In March 1886, Browns owner Chris von der Ahe offered Barkley for $1000 to Allegheny, the first team to pay the money. Billy Barnie, the manager of the Baltimore Orioles, was able to have Barkley sign an undated contract with his team and wired the $1000 asking price to Von der Ahe. However Von der Ahe had already secured a deal with McKnight, who was still the Alleghenys' owner. Barkley was convinced by Von der Ahe to play for the Allegheny club instead of Baltimore. However the Orioles appealed the decision by McKnight, who used his position as the president of American Association to decide where Barkley would play. It was later decided that the American Association would suspend and fine Barkley for signing with Allegheny. However McKnight refused Barkley's punishment and did not tell Barkley he would be suspended for the year. Barkley sued the Association, but they settled out of court with the suspension being lifted although the fine stayed in place. Baltimore was offered and accepted Milt Scott as payment. For his role in the controversy, McKnight was ousted as American Association president. This then led Allegheny president William A. Nimick to move the team from the American Association to the National League.
The Alleghenys were severely crippled during their 1890 season, when nearly all of their stars jumped to the Pittsburgh Burghers of the Players' League. With a decimated roster, the team experienced what is still the worst season in franchise history, going 23-113. The battle nearly ruined McKnight, and he was forced to return his franchise to the league. However, almost immediately after this, McKnight joined the backers of the Burghers as a minority owner, which then repurchased the Pittsburgh National League franchise and rechartered it under a different corporate name. Once the upstart league folded that season, the Alleghenys were thus able to legally recover the services of most of the players who had jumped to the Players' League a year earlier.
