Tiernan's debut major league game was on April 30, 1887. On June 15 of that season, he scored six
runs in a single game, and is one of only a handful of major league players to have accomplished that feat. Tiernan was nicknamed "Silent Mike" because he generally avoided the press and did not protest when umpires made questionable calls. Tiernan led the
National League in home runs in 1890 and 1891, and compiled a .311 lifetime batting average. His final game was played on July 31, 1899. He is the Giants' all-time franchise leader in triples and stolen bases. One of the great
home run hitters of the 19th century, he hit 106 of them, which ties him with
Hall of Famer Dan Brouthers for fourth most among 19th century ball players. ==Later life==