Singles
1991 ATP German Open
Final
Champion	Karel Nováček[1]
Runner-up	Magnus Gustafsson
Score	6–3, 6–3, 5–7, 0–6, 6–1
Details
Draw	56
Seeds	16
Events
Singles Doubles
← 1990 · ATP German Open · 1992 →

Karel Nováček defeated Magnus Gustafsson in the final, 6–3, 6–3, 5–7, 0–6, 6–1 to win the singles tennis title at the 1991 Hamburg European Open.

Juan Aguilera was the defending champion, but lost in the first round to Jordi Arrese.^[2]

	Quarterfinal							Semifinal							Final
	1	Stefan Edberg	2	64
	9	Michael Stich	6	7
								9	Michael Stich	3	6	65
								13	Karel Nováček	6	2	7
	13	Karel Nováček	4	6	6
		Mark Koevermans	6	4	2
															13	Karel Nováček	6	6	5	0	6
																Magnus Gustafsson	3	3	7	6	1
		Goran Prpić	7	3
	4	Goran Ivanišević	5	0r
									Goran Prpić	2	6	64
									Magnus Gustafsson	6	1	7
		Magnus Gustafsson	6	6
	WC	Yannick Noah	1	4

	First round							Second round							Third round							Quarterfinal
								1	S Edberg	6	6
	WC	A Mronz	6	7				WC	A Mronz	3	1
	WC	P Kühnen	2	5											1	S Edberg	6	6
		N Kulti	4	64												R Agénor	2	1
		R Agénor	6	7					R Agénor	7	0	6
		A Krickstein	4	6	6				A Krickstein	5	6	2
	16	M Rosset	6	2	3																	1	S Edberg	2	64
	9	M Stich	1	6	7																	9	M Stich	6	7
		T Carbonell	6	3	5			9	M Stich	7	6
	Q	T Nijssen	6	4	64				P Haarhuis	5	0
		P Haarhuis	3	6	7										9	M Stich	6	6
	Q	F Clavet	7	6												F Clavet	1	4
		A Mansdorf	64	2				Q	F Clavet	6	4	6
								8	E Sánchez	3	6	4

	First round							Second round							Third round							Quarterfinal
								3	P Sampras	6	4	6
		H Skoff	7	6					H Skoff	3	6	4
		T Muster	5	2											9	P Sampras	4	2
		O Camporese	7	6											13	K Nováček	6	6
	Q	R Haas	64	4					O Camporese	3	2
	WC	C-U Steeb	4	64				13	K Nováček	6	6
	13	K Nováček	6	7																		13	K Nováček	4	6	6
	11	Gómez	4	3																			M Koevermans	6	4	2
		F Davín	6	6					F Davín	4	4
		M Koevermans	6	6					M Koevermans	6	6
		M Vajda	3	2												M Koevermans	6	6
		M Jaite	5	3											5	S Bruguera	4	3
		E Jelen	7	6					E Jelen	3	1
								5	S Bruguera	6	6

	First round							Second round							Third round							Quarterfinal
								6	J Courier	7	2	4
		H de la Peña	6	3	6				H de la Peña	63	6	6
		C Bergström	2	6	2											H de la Peña	3	4
		J Aguilera	2	5												G Prpić	6	6
		J Arrese	6	7					J Arrese	3	3
		G Prpić	6	6					G Prpić	6	6
	12	A Chesnokov	4	3																			G Prpić	7	3
	14	A Volkov	6	7																		4	G Ivanišević	5	0r
		G Bloom	1	612				14	A Volkov	7	7
		A Järryd	4	1				Q	A Boetsch	64	61
	Q	A Boetsch	6	6											14	A Volkov	1	3
	WC	U Riglewski	1	4											4	G Ivanišević	6	6
		L Mattar	6	6					L Mattar	1	1
								4	G Ivanišević	6	6

	First round							Second round							Third round							Quarterfinal
								7	J Svensson	2	2
	Q	C Pistolesi	3	3					C Caratti	6	6
		C Caratti	6	6												C Caratti	5	6	2
		M Gustafsson	6	6												M Gustafsson	7	3	6
		D Engel	4	2					M Gustafsson	3	6	6
		H Leconte	63	3				10	A Cherkasov	6	4	4
	10	A Cherkasov	7	6																			M Gustafsson	6	6
	LL	W Ferreira	2	6	3																	WC	Y Noah	1	4
		M Larsson	6	3	6				M Larsson	4	6	3
	WC	Y Noah	7	6				WC	Y Noah	6	1	6
		R Fromberg	66	0											WC	Y Noah	1	6	6
		M Filippini	3	3											Q	R Furlan	6	4	3
	Q	R Furlan	6	6				Q	R Furlan	7	6
								2	I Lendl	5	4

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