Unglaub then played in the minor leagues for six more years before he was killed in an accident while working at Baltimore's Pennsylvania Railroad shops.

In his formative years, he served as batboy and mascot for the ballclub, receiving baseball tips and advice from players such as John McGraw, Joe Kelley, Willie Keeler, and Steve Brodie.

Accepting the offer, Unglaub attended the school for three years, pitching under his middle name of Alexander and acquiring an engineering degree.

During his time in college, Unglaub also played for a variety of amateur and semipro teams on Maryland's Eastern Shore.

[5] Following a good performance in Meriden's 14-6 win against Waterbury in their last home game on September 7, Unglaub was sold to Worcester Farmers of the Eastern League.

While he verbally agreed to stay with Worcester for another year and received approximately $50 in advance money from the club's president, he went on trial with Philadelphia Phillies and signed a contract with them in January 1902.

[11] Refusing to return to Worcester, Unglaub crossed the country to join the Sacramento Senators of the independent California State League for the upcoming 1902 season.

Though initially signed by the Boston Americans, his rights were transferred to New York in an unknown transaction before the season started.

[a][1] Unglaub made his major league debut on April 15, pinch-hitting and taking over at shortstop in a 4–1 loss to Boston.

[15][16] Still not having played since May 6, he was sent back to the Americans in late July as a player to be named later from an earlier trade for Patsy Dougherty.

[16] On July 4, 1905, Unglaub played all 20 innings at first base in a pitching duel between Cy Young of the Americans and Rube Waddell of the Philadelphia Athletics.

[1][17] Much of his playing time came at the end of the year, when he replaced player-manager Jimmy Collins at third base in the second game of a doubleheader against the St. Louis Browns on September 22, then served as the starting third baseman for the rest of the season, batting .288 with 13 runs scored and six runs batted in (RBI) in the season's final 16 games.

Unglaub was unable to take advantage of the offer, however, because the league became affiliated with organized baseball again in 1907, and his contract was transferred back to Boston.

[2] The Red Sox were struggling to find a manager, as Chick Stahl, who previously served in that capacity, committed suicide during spring training.

Unglaub did not immediately report to his new team, claiming that they had failed to communicate with him and threatening to join the independent Stockton Millers unless he was guaranteed the same salary he had made in Boston.

"[1] Though not the best at fielding, he could (and did) play a variety of positions, covering at third and first while Bill Shipke and Jerry Freeman were struggling and filling in for an injured Jim Delahanty at second base and a hurt Clyde Milan in the outfield.

"[2] In May, Unglaub missed some time with broken ribs, reportedly caused when Bob Ganley hit him with a baseball bat in a brawl.

[20] Before the 1911 season, the Senators sold Unglaub's contract to the Lincoln Railsplitters of the Western League, where he played and managed.

After a season with them, he split 1912 between the Baltimore Orioles (now an International League team) and the Minneapolis Millers of the American Association.

On November 29, 1916, he was supervising repair work on a locomotive when an accident occurred that crushed and mangled his body, killing him.