5‑Nov‑1990 | Itaparica | Hard | R32 | 131 | 109 | Nuno Marques [POR] d. Mancini | 6-0 6-7 6-4 | | | | | | | | | |
29‑Oct‑1990 | Rio De Janeiro CH | Hard | R32 | 105 | 246 | (WC)Mauro Menezes [BRA] d. (5)Mancini | 4-6 6-1 6-1 | | | | | | | | | |
21‑Sep‑1990 | Davis Cup WG SF: AUS vs ARG | Grass | RR | 78 | 91 | Pat Cash [AUS] d. Mancini | 6-1 6-1 6-2 | | | | | | | | | |
27‑Aug‑1990 | US Open | Hard | R128 | 60 | 85 | Malivai Washington [USA] d. Mancini | 6-2 6-4 6-3 | | | | | | | | | |
20‑Aug‑1990 | Schenectady | Hard | R16 | 59 | 423 | (WC)Chuck Adams [USA] d. (4)Mancini | 6-1 6-4 | | | | | | | | | |
23‑Jul‑1990 | Hilversum | Clay | R32 | 53 | 41 | Paul Haarhuis [NED] d. Mancini | 6-2 6-2 | | | | | | | | | |
16‑Jul‑1990 | Stuttgart Outdoor | Clay | R64 | 51 | 60 | Jimmy Arias [USA] d. Mancini | 6-4 6-3 | | | | | | | | | |
9‑Jul‑1990 | Gstaad | Clay | R32 | 52 | 44 | Sergi Bruguera [ESP] d. Mancini | 6-3 6-4 | | | | | | | | | |
11‑Jun‑1990 | Florence | Clay | R16 | 52 | 78 | Aki Rahunen [FIN] d. (3)Mancini | 2-6 6-2 6-3 | | | | | | | | | |
11‑Jun‑1990 | Florence | Clay | R32 | 52 | 199 | (3)Mancini d. (Q)Marcos Aurelio Gorriz [ESP] | 6-2 7-6 | | | | | | | | | |
28‑May‑1990 | Roland Garros | Clay | R64 | 32 | 34 | Franco Davin [ARG] d. Mancini | 6-3 5-7 7-5 6-1 | | | | | | | | | |
28‑May‑1990 | Roland Garros | Clay | R128 | 32 | 12 | Mancini d. (9)Jay Berger [USA] | 6-4 6-2 6-2 | | | | | | | | | |
21‑May‑1990 | Dusseldorf | Clay | RR | 32 | 24 | Mancini d. Jonas Svensson [SWE] | 6-4 6-2 | | | | | | | | | |
21‑May‑1990 | Dusseldorf | Clay | RR | 32 | 43 | Goran Ivanisevic [CRO] d. Mancini | 6-4 6-0 | | | | | | | | | |
21‑May‑1990 | Dusseldorf | Clay | RR | 32 | 227 | Mancini d. Thomas Buchmayer [AUT] | 6-2 6-4 | | | | | | | | | |
14‑May‑1990 | Rome Masters | Clay | QF | 24 | 15 | (8)Andrei Chesnokov [RUS] d. (16)Mancini | 7-6 6-0 | | | | | | | | | |
14‑May‑1990 | Rome Masters | Clay | R16 | 24 | 5 | (16)Mancini d. (1)Brad Gilbert [USA] | 6-2 6-1 | | | | | | | | | |
14‑May‑1990 | Rome Masters | Clay | R32 | 24 | 37 | (16)Mancini d. Henri Leconte [FRA] | 6-4 6-4 | | | | | | | | | |
14‑May‑1990 | Rome Masters | Clay | R64 | 24 | 108 | (16)Mancini d. (LL)Christian Miniussi [ARG] | 4-6 7-6 6-4 | | | | | | | | | |
7‑May‑1990 | Hamburg Masters | Clay | R64 | 25 | 74 | (WC)Jens Woehrmann [GER] d. (16)Mancini | 6-0 6-2 | | | | | | | | | |
30‑Apr‑1990 | Madrid | Clay | QF | 23 | 14 | (4)Martin Jaite [ARG] d. (5)Mancini | 6-3 3-6 6-2 | | | | | | | | | |
30‑Apr‑1990 | Madrid | Clay | R16 | 23 | 108 | (5)Mancini d. Cassio Motta [BRA] | 6-3 6-4 | | | | | | | | | |
30‑Apr‑1990 | Madrid | Clay | R32 | 23 | 52 | (5)Mancini d. Luiz Mattar [BRA] | 6-4 2-6 6-3 | | | | | | | | | |
23‑Apr‑1990 | Monte Carlo Masters | Clay | R32 | 17 | 152 | (WC)Henri Leconte [FRA] d. (11)Mancini | 6-4 6-4 | | | | | | | | | |
23‑Apr‑1990 | Monte Carlo Masters | Clay | R64 | 17 | 26 | (11)Mancini d. Christo Van Rensburg [RSA] | 6-2 6-4 | | | | | | | | | |
16‑Apr‑1990 | Nice | Clay | R32 | 17 | 116 | (Q)Claudio Pistolesi [ITA] d. (2)Mancini | 6-4 6-3 | | | | | | | | | |
9‑Apr‑1990 | Barcelona | Clay | R16 | 17 | 123 | (Q)Diego Perez [URU] d. (5)Mancini | 6-4 6-1 | | | | | | | | | |
9‑Apr‑1990 | Barcelona | Clay | R32 | 17 | 82 | (5)Mancini d. Aki Rahunen [FIN] | 7-6 0-6 6-4 | | | | | | | | | |
30‑Mar‑1990 | Davis Cup WG QF: ARG vs GER | Clay | RR | 16 | 82 | Mancini d. Jens Woehrmann [GER] | 7-5 4-6 7-6(2) 7-6(2) | | | | | | | | | |
30‑Mar‑1990 | Davis Cup WG QF: ARG vs GER | Clay | RR | 16 | 14 | Mancini d. Carl Uwe Steeb [GER] | 7-6(6) 6-3 6-4 | | | | | | | | | |
16‑Mar‑1990 | Miami Masters | Hard | R64 | 14 | 199 | (Q)Bryan Shelton [USA] d. (11)Mancini | 6-4 7-6 | | | | | | | | | |
5‑Mar‑1990 | Indian Wells Masters | Hard | R64 | 14 | 139 | Michiel Schapers [NED] d. (11)Mancini | 6-4 6-1 | | | | | | | | | |
26‑Feb‑1990 | Rotterdam | Carpet | R32 | 14 | 96 | (Q)Thomas Hogstedt [SWE] d. (2)Mancini | 6-7 6-4 6-2 | | | | | | | | | |
2‑Feb‑1990 | Davis Cup WG R1: ARG vs ISR | Clay | RR | 12 | 89 | Mancini d. Gilad Bloom [ISR] | 6-2 7-6(2) 6-2 | | | | | | | | | |