ATP Miami 03/24 15:00 24 [54] Daniel Altmaier v Jan-Lennard Struff [25] 3-6,3-6
ATP Miami 03/21 15:00 23 [54] Daniel Altmaier v Harold Mayot [141] 6-2,7-5
ATP Indian Wells 03/07 21:10 23 [273] Lucas Pouille v Daniel Altmaier [53] 6-4,6-3
ATP Acapulco 02/29 01:25 26 [57] Daniel Altmaier v Miomir Kecmanovic [53] 4-6,4-6
ATP Acapulco 02/28 03:30 25 [6] Alexander Zverev v Daniel Altmaier [57] 3-6,6-3,3-6
ATP Buenos Aires 02/12 17:00 25 [87] Facundo Diaz Acosta v Daniel Altmaier [53] 6-3,7-6
ATP Cordoba 02/06 17:00 25 [93] Federico Coria v Daniel Altmaier [52] 5-7,6-3,6-4
Australian Open 01/15 04:25 23 [50] Daniel Altmaier v Karen Khachanov [15] 7-5,3-6,6-7,6-7
ATP Auckland 01/11 05:30 27 [35] Arthur Fils v Daniel Altmaier [57] Retired
ATP Auckland 01/09 23:00 26 [57] Daniel Altmaier v Felix Auger Aliassime [27] 7-6,7-5
ATP Auckland 01/07 23:00 25 [56] Daniel Altmaier v Marcos Giron [60] 7-6,6-2
ATP Brisbane 01/04 05:30 26 [56] Daniel Altmaier v Grigor Dimitrov [14] 1-6,2-6
ATP Brisbane 01/02 06:00 25 [225] Li Tu v Daniel Altmaier [56] 6-7,6-7
ATP Metz 11/07 13:20 25 [54] Daniel Altmaier v Mate Valkusz [232] 2-6,2-6
ATP Metz 11/05 13:00 25 Daniel Altmaier v Hugo Gaston Cancelled
ATP Paris 11/02 21:30 26 [54] Daniel Altmaier v Holger Rune [7] 3-6,3-6
ATP Paris 11/01 09:00 25 Taylor Fritz v Daniel Altmaier Walkover
ATP Paris 10/31 13:00 24 [54] Daniel Altmaier v Arthur Fils [36] 6-2,6-4
ATP Paris 10/28 08:00 14 Daniel Altmaier v Bernabe Zapata Miralles Cancelled
ATP Vienna 10/25 12:00 25 [89] Gael Monfils v Daniel Altmaier [47] 6-4,6-4
ATP Tokyo 10/16 12:40 25 [12] Tommy Paul v Daniel Altmaier [48] 3-6,6-1,6-3
ATP Shanghai 10/04 04:30 23 [49] Daniel Altmaier v Yoshihito Nishioka [38] 4-6,6-3,6-7
ATP Beijing 09/26 04:55 14 [162] Lloyd Harris v Daniel Altmaier [49] 6-3,6-1
Davis Cup 09/17 10:20 4 [157] Damir Dzumhur v Daniel Altmaier [49] Cancelled
Davis Cup 09/16 10:00 1 [218] Nerman Fatic v Daniel Altmaier [49] 6-7,2-6
US Open 08/31 15:00 24 [12] Alexander Zverev v Daniel Altmaier [53] 7-6,3-6,6-4,6-3
US Open 08/29 16:45 23 [53] Daniel Altmaier v Constant Lestienne [101] 6-7,6-3,6-1,6-2
ATP Cincinnati 08/15 15:00 24 [58] Alexei Popyrin v Daniel Altmaier [52] 6-7,6-4,6-4
ATP Cincinnati 08/13 14:00 19 [52] Daniel Altmaier v Corentin Moutet [79] 4-6,4-6
ATP Cincinnati 08/12 14:00 14 [52] Daniel Altmaier v Christopher O'Connell [73] 3-6,7-6,6-4

Wikipedia - Daniel Altmaier

Daniel Altmaier (German pronunciation: [ˈdaːni̯eːl ˈaltmaɪ̯ɐ]; born 12 September 1998) is a German professional tennis player. He has a career high ATP singles ranking of world No. 47, achieved on 2 October 2023. He is the current German No. 4.