As of January, 18
Code:
Bernard Tomic (AUS) 289
Yuki Bhambri (IND) 332
Filip Krajinović (SRB) 336
Ryan Harrison (USA) 341 (career high)
Nikoloz Basilashvili (GEO) 554
Javier Martí (ESP) 682
Jack Sock (USA) 697 (career high)
David Souto (VEN) 701 (career high)
Facundo Argüello (ARG) 737 (career high)
Arthur De Greef (BEL) 834
Agustín Velotti (ARG) 837
Andrea Collarini (ARG) 870 (career high)
Dovydas Sakinis (LTU) 871 (career high)
Martín Cuevas (URU) 882 (career high)
Suk-Young Jeong (KOR) (1993) 891 (career high)
Guilherme Clezar (BRA) 938 (career high)
Duilio Beretta (PER) 942
Tiago Fernandes (BRA) (1993) 945 (career high)
Johannes Robert Van Overbeek(USA) 946
Federico Gaio (ITA) 957
Jordan Cox (USA) 980