2021 Sofia Open – Singles

Jannik Sinner was the defending champion and successfully defended his title, defeating Gaël Monfils in the final, 6–3, 6–4.^[1]

Singles
2021 Sofia Open
Champion	Jannik Sinner
Runner-up	Gaël Monfils
Score	6–3, 6–4
Draw	28 (4 Q / 3 WC )
Seeds	8

Main article: 2021 Sofia Open

Seeds

The top four seeds received a bye into the second round.

1. Jannik Sinner (champion)
2. Gaël Monfils (final)
3. Alex de Minaur (second round)
4. Alexander Bublik (withdrew)
5. Filip Krajinović (semifinals)
6. Adrian Mannarino (first round)
7. Alejandro Davidovich Fokina (first round)
8. John Millman (quarterfinals)

Draw

Key

• Q = Qualifier
• WC = Wild card
• LL = Lucky loser
• Alt = Alternate
• ITF = ITF entry
• PR = Protected ranking
• SR = Special ranking
• SE = Special exempt
• JE = Junior exempt
• JR = Junior Accelerator Programme entrant
• CO = College Accelerator Programme entrant
• NG = Next Gen Accelerator Program entrant
• w/o = Walkover
• r = Retired
• d = Defaulted

Finals

	Semifinals							Final
	1	Jannik Sinner	6	7
	5	Filip Krajinović	3	5
								1	Jannik Sinner	6	6
								2	Gaël Monfils	3	4
		Marcos Giron	5	0
	2	Gaël Monfils	7	6

Top half

	First round							Second round							Quarterfinals							Semifinals
								1	J Sinner	6	77
	Q	E Gerasimov	5	710	6			Q	E Gerasimov	2	63
		V Pospisil	7	68	3										1	J Sinner	77	6
		E Ruusuvuori	6	4	4											J Duckworth	64	4
		J Duckworth	3	6	6				J Duckworth	6	6
		B Paire	6	7					B Paire	4	4
	7	A Davidovich Fokina	4	5																		1	J Sinner	6	7
																						5	F Krajinović	3	5
								LL	K Majchrzak	7	6
	WC	D Kuzmanov	64	77	6			WC	D Kuzmanov	5	1
		L Musetti	77	63	3										LL	K Majchrzak	3	6	3
	Q	P Martínez	65	3											5	F Krajinović	6	4	6
		L Đere	77	6					L Đere	3	0
	WC	A Lazarov	0	3				5	F Krajinović	6	6
	5	F Krajinović	6	6

Bottom half

	First round							Second round							Quarterfinals							Semifinals
	8	J Millman	6	6
		M Ymer	2	4				8	J Millman	5	77	6
	Q	A Seppi	4	2				Q	I Marchenko	7	60	3
	Q	I Marchenko	6	6											8	J Millman	4	2
		J Munar	77	1	4											M Giron	6	6
		M Giron	62	6	6				M Giron	77	77
								3	A de Minaur	65	62
																							M Giron	5	0
	6	A Mannarino	3	2																		2	G Monfils	7	6
		G Mager	6	6					G Mager	77	6
		M Kecmanović	79	6					M Kecmanović	63	3
	WC	A Andreev	67	4												G Mager	2	2
		I Ivashka	6	6											2	G Monfils	6	6
		P Andújar	4	3					I Ivashka
								2	G Monfils	w/o

Qualifying

Seeds

1. Pedro Martínez (qualified)
2. Marco Cecchinato (first round)
3. Andreas Seppi (qualified)
4. Egor Gerasimov (qualified)
5. Daniel Elahi Galán (first round)
6. Kamil Majchrzak (qualifying competition, lucky loser)
7. Tomáš Macháč (qualifying competition)
8. Jurij Rodionov (first round)

Qualifiers

1. Pedro Martínez
2. Illya Marchenko
3. Andreas Seppi
4. Egor Gerasimov

Lucky loser

1. Kamil Majchrzak

Qualifying draw

First qualifier

	First round							Qualifying competition
	1	Pedro Martínez	7	6
	WC	Simon Anthony Ivanov	5	1
								1	Pedro Martínez	6	77
								6	Kamil Majchrzak	4	64
		Maxime Cressy	6	4	3
	6	Kamil Majchrzak	4	6	6

Second qualifier

	First round							Qualifying competition
	2	Marco Cecchinato	3	3
		Illya Marchenko	6	6
									Illya Marchenko	3	6	77
								7	Tomáš Macháč	6	3	62
		Kacper Żuk	4	2
	7	Tomáš Macháč	6	6

Third qualifier

	First round							Qualifying competition
	3	Andreas Seppi	77	6
		Cem İlkel	63	2
								3	Andreas Seppi	6	6
								WC	Alexander Donski	3	2
	WC	Alexander Donski	2	6	77
	8	Jurij Rodionov	6	1	64

Fourth qualifier

	First round							Qualifying competition
	4	Egor Gerasimov	6	77
		Evgeny Donskoy	3	64
								4	Egor Gerasimov	78	6
									Altuğ Çelikbilek	66	3
		Altuğ Çelikbilek	78	4	7
	5	Daniel Elahi Galán	66	6	5