Singles
2023 Open de Oeiras
Champion	Zsombor Piros
Runner-up	Juan Manuel Cerúndolo
Score	6–3, 6–4

Kaichi Uchida was the defending champion^[1] but lost in the quarterfinals to Juan Manuel Cerúndolo.

Zsombor Piros won the title after defeating Cerúndolo 6–3, 6–4 in the final.

Seeds

Draw

Finals

	Semifinals							Final
	7/SE	Zsombor Piros	6	6
	3	Sebastian Ofner	4	2
								7/SE	Zsombor Piros	6	6
								4	Juan Manuel Cerúndolo	3	4
	4	Juan Manuel Cerúndolo	6	6
	WC	Pedro Sousa	2	4

Top half

	First round							Second round							Quarterfinals							Semifinals
	1	A Mannarino	5	7	6
		A Lazarov	7	5	2			1	A Mannarino	6	2	3
		K Coppejans	6	6					K Coppejans	4	6	6
	Q	Jaime Faria	2	2												K Coppejans	0	2
	Q	Daniel Mérida	6	6											7/SE	Z Piros	6	6
	Q	Cezar Crețu	4	4				Q	D Mérida	4	3
		D Sweeny	2	4				7/SE	Z Piros	6	6
	7/SE	Z Piros	6	6																		7/SE	Z Piros	6	6
	3	S Ofner	6	6																		3	S Ofner	4	2
	Q	P Nouza	3	4				3	S Ofner	2	6	6
		J McCabe	2	6	77				J McCabe	6	1	2
	Alt	J Domingues	6	3	63										3	S Ofner	5	6	6
		C-h Tseng	6	6											8	A Vavassori	7	3	4
	LL	H Squire	2	3					C-h Tseng	3	1
		F Ferreira Silva	2	0				8	A Vavassori	6	6
	8	A Vavassori	6	6

Bottom half

	First round							Second round							Quarterfinals							Semifinals
	6	K Uchida	6	77
		J De Loore	4	63				6	K Uchida	6	1	6
		H Mayot	3	4					A Andreev	1	6	2
		A Andreev	6	6											6	K Uchida	3	3
		M Guinard	1	0r											4	JM Cerúndolo	6	6
	Q	P Llamas Ruiz	6	3				Q	P Llamas Ruiz	4	3
	WC	D Vale	4	4				4	JM Cerúndolo	6	6
	4	JM Cerúndolo	6	6																		4	JM Cerúndolo	6	6
	5	J Sousa	1	3																		WC	P Sousa	2	4
		S Diez	6	6					S Diez	77	6
		E Furness	7	77					E Furness	62	1
	Q	B Harris	5	63												S Diez	5	6	3
	WC	P Sousa	6	6											WC	P Sousa	7	3	6
	WC	H Rocha	3	4				WC	P Sousa	7	77
		FC Jianu	4	63				2	A Müller	5	64
	2	A Müller	6	77

References

External links

• Main draw
• Qualifying draw