Singles
1991 BMW Open
Final
Champion	Magnus Gustafsson
Runner-up	Guillermo Pérez Roldán
Score	3–6, 6–3, 4–3 ret
Details
Draw	32
Seeds	8
Events
Singles Doubles
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The 1991 BMW Open Singles was the singles bracket of the 1991 BMW Open. The title was won by Magnus Gustafsson, defeating Guillermo Pérez Roldán. Roldán retired while Gustafsson was leading 3–6, 6–3, 4–3.^{[clarification needed]} Karel Nováček, the defending champion from the prior year singles event, did not participate.^[1]

	Semifinals							Final
	1	Ivan Lendl	4	5
		Magnus Gustafsson	6	7
									Magnus Gustafsson	3	6	4
								7	Guillermo Pérez Roldán	6	3	3r
		Christian Bergström	0	0
	7	Guillermo Pérez Roldán	6	6

	First round							Second round							Quarterfinals							Semifinals
	1	I Lendl	6	6
		A Mronz	2	2				1	I Lendl	3	6	6
		M Woodforde	3	2					G Prpić	6	4	2
		G Prpić	6	6											1	I Lendl	3	6	7
	LL	E Bengoechea	4	7	6											T Witsken	6	4	5
		H de la Peña	6	5	1			LL	E Bengoechea	4	6	4
		T Witsken	1	7	6				T Witsken	6	3	6
	8	A Volkov	6	5	1																	1	I Lendl	4	5
	3	J Svensson	4	1																			M Gustafsson	6	7
		A Järryd	6	6					A Järryd	6	4	63
	WC	A Mancini	4	3				WC	U Riglewski	4	6	77
	WC	U Riglewski	6	6												U Riglewski	2	5
		A Mansdorf	4	2												M Gustafsson	6	7
		H Skoff	6	6					H Skoff	0	6	4
		M Gustafsson	5	6	6				M Gustafsson	6	4	6
	6	M Stich	7	4	3

	First round							Second round							Quarterfinals							Semifinals
	5	T Muster	1	6	3
		C Bergström	6	2	6				C Bergström	6	6
		M Vajda	77	6					M Vajda	2	4
		C-U Steeb	63	2												C Bergström	4	6	6
	Q	A Medvedev	3	5												L Jönsson	6	2	0
		L Jönsson	6	7					L Jönsson	6	6
	Q	D Pescariu	6	6				Q	D Pescariu	0	4
	4	J McEnroe	2	2																			C Bergström	0	0
	7	G Pérez Roldán	6	6																		7	G Pérez Roldán	6	6
		J Aguilera	3	0				7	G Pérez Roldán	7	6
	Q	D Engel	6	6				Q	D Engel	5	2
	Q	P Vojtíšek	3	3											7	G Pérez Roldán	77	6
		E Jelen	3	6	6										2	G Ivanišević	65	1
		R Agénor	6	4	0				E Jelen	4	6	3
	WC	J Wöhrmann	62	1				2	G Ivanišević	6	4	6
	2	G Ivanišević	77	6

• Singles draw