Chicago Cubs top prospect Javier Baez underwent tests on Monday after injuring his thumb in the Arizona Fall League, according to CSN Chicago's David Kaplan.

The tests were done to determine if Baez broke the tip of his thumb. If the thumb is broken, it's likely that Baez will miss the rest of the fall.

Baez, a 19-year-old infielder, is considered one of the top 50 players in minor league baseball. Chicago selected him with their No. 1 pick in 2011, and he has seen time at both shortstop and third base in the Cubs' system. Shortstop is Baez's natural position, but with Starlin Castro around, it's likely the youngster makes a more permanent move to third.

Baez hit .333 with 12 home runs at Class A Peoria this year before being promoted to High A Daytona. He did struggle a bit in Daytona, hitting just .188 in 23 games. In the Fall League, he is hitting .211 with four home runs.