Singles
2018 Knoxville Challenger
Champion	Reilly Opelka
Runner-up	Bjorn Fratangelo
Score	7–5, 4–6, 7–6(7–2)

Filip Peliwo was the defending champion but chose not to defend his title.

Reilly Opelka won the title after defeating Bjorn Fratangelo 7–5, 4–6, 7–6^(7–2) in the final.

Seeds

Draw

Finals

	Semifinals							Final
		Nikola Milojević	3	4
	8	Reilly Opelka	6	6
								8	Reilly Opelka	7	4	77
									Bjorn Fratangelo	5	6	62
		Christopher Eubanks	64	4
		Bjorn Fratangelo	77	6

Top half

	First round							Second round							Quarterfinals							Semifinals
	1/WC	T Sandgren	6	6
		H Laaksonen	3	0				1/WC	T Sandgren	4	4
		R Quiroz	64	4					B Rola	6	6
		B Rola	77	6												B Rola	4	2
		N Serdarušić	2	4												N Milojević	6	6
		N Milojević	6	6					N Milojević	6	6
	WC	Timo Stodder	1	3				6	J Jung	0	4
	6	J Jung	6	6																			N Milojević	3	4
	4	M Mmoh	6	6																		8	R Opelka	6	6
	Q	Evan Song	2	3				4	M Mmoh	6	6
	Q	M Ymer	6	6				Q	M Ymer	3	2
		K Majchrzak	4	4											4	M Mmoh
	Q	Mi Redlicki	77	6											8	R Opelka	w/o
		M Arévalo	65	4				Q	Mi Redlicki	610	66
	Q	E Gómez	2	3				8	R Opelka	712	78
	8	R Opelka	6	6

Bottom half

	First round							Second round							Quarterfinals							Semifinals
	7	P Polansky	6	6
	Alt	C Harrison	2	2				7	P Polansky	3	4
		C Eubanks	7	63	6				C Eubanks	6	6
	WC	J. J. Wolf	5	77	4											C Eubanks	4
	WC	Preston Touliatos	3	2												E Karlovskiy	1r
		E Karlovskiy	6	6					E Karlovskiy	5	6	6
		JC Aragone	2	67				3	B Klahn	7	4	4
	3	B Klahn	6	79																			C Eubanks	64	4
	5	T Smyczek	3	6	6																		B Fratangelo	77	6
		J-P Smith	6	3	2			5	T Smyczek	6	77
		D Köpfer	6	2	6				D Köpfer	4	64
	Alt	M Krueger	1	6	2										5	T Smyczek	2	1
	SE	T Paul	4	4												B Fratangelo	6	6
		B Fratangelo	6	6					B Fratangelo	77	64	6
		T Kamke	6	3	6				T Kamke	64	77	4
	2	M Granollers	4	6	4

References

• Main Draw
• Qualifying Draw