He earned the nickname "Sure Shot" for the strength and accuracy of his throws to first base, and was also sometimes referred to in the 1880s as the "King of Second Basemen."
While playing for Cleveland, he also compiled batting averages of .325 and .326 in 1881 and 1883 and led the league in assists by a second baseman and range factor.
When the Union Association was formed in 1884, Dunlap was lured to play for the St. Louis Maroons where he became the highest paid player in baseball.
After three years in St. Louis, Dunlap was sold to the Detroit Wolverines and helped that team win the 1887 National League pennant.
Dunlap remained with the Blues for four seasons and consistently ranked as one of the leading hitters and defensive second basemen in the National League.
So key was he to the Blues that one writer observed, "The Maroons without Dunlap are like the play of Hamlet without the melancholy Dane.
[1] One account described Dunlap's throwing prowess as follows: "[E]ndless practice made him adept as a monkey at grabbing a sizzling ground ball in either hand and firing it off from the very spot he seized it.
In his book on the history of the home run, Mark Ribowsky wrote that the nickname dated back to a game against the Chicago White Stockings on July 10, 1880.
The White Stockings had won 21 straight games until Dunlap hit a walk-off two-run home run in the bottom of the ninth inning.
The team compiled a record of 94-19, and Dunlap led the new league in most significant offensive and defensive categories.
[4] Some baseball historians have suggested that Dunlap's accomplishments during the 1884 season should be discounted due to the lesser talent pool in the Union Association.
Although his batting average dropped 142 points to .270 in 1885, Dunlap continued to be one of the best defensive second basemen in the major leagues.
He led the National League's second basemen in 1885 with a .934 fielding percentage and ranked second in assists (374), putouts (314), and range factor (6.49).
In early August 1886, Dunlap was sold to the Detroit Wolverines for $4,700, the most expensive purchase price at the time.
"[17] For the 1886 season, Dunlap led the National League with a career high 393 assists, more than any NL player at any position.
In 1887, Dunlap's defensive play at second base helped lead the Detroit Wolverines to the NL pennant with a record of 79-45.
... Dunlap is one of the most active men on the field, and is of great value to a team on account of his ability as a kicker and coacher.
"[3] Before the last game of the World Series had been played, rumors spread that Detroit (which had amassed an all-star lineup with a commensurate payroll) was in negotiations to unload Dunlap's high salary by selling him to Pittsburgh.
[22] Dunlap announced in November 1887 that he would not consent unless the Detroit club paid him half of the sum it was to receive from Pittsburgh to secure his release.
He told the reporter that the Detroit club had three choices -- "give me half of the money secured for my release, allow me to go where I please, or fulfill the contract made with me last year.
[24] His total annual compensation on signing with Pittsburgh was $6,000, making him the highest paid player in baseball history to that time.
[25] The Detroit Free Press congratulated the "cranks" of Pittsburgh for their team's acquisition of "no less than the king second baseman of the country.
Aside from his batting average, disagreements with Pittsburgh's manager, Guy Hecker, reportedly contributed to the decision.
[6] At the time, the Washington correspondent for Sporting Life predicted that Dunlap would bring bad luck to his new team.
Dunlap returned the notice and filed a grievance, contending he should have been continued at least on half pay since he was disabled while sliding into a base.
... Dunlap was a real infielder of the type so popular ten years ago -- one of the solid, bulky style through whom no grounder seemed able to pass, but who could nevertheless wave the hot ones goodbye with graceful ease when occasion demanded.
In his 1910 book on the history of baseball, Alfred Henry Spink, the founder of The Sporting News, was unequivocal: "I have seen all the great second basemen ...
"[36] In 1910, John Montgomery Ward, a Hall of Fame inductee who played from 1878 to 1894, published an article about the greatest infielders in baseball history.
He was something of a grandstand player, because of his tendency to make one-handed catches and stops but he got there just the same and was a big favorite wherever he showed.
[11] Dunlap's career range factor of 6.31 at second base still ranks as the fifth highest in the history of Major League Baseball.