2018 Keio Challenger – Men's singles

Yūichi Sugita was the defending champion but chose not to defend his title.

Men's singles
2018 Keio Challenger
Champion	Yasutaka Uchiyama
Runner-up	Tatsuma Ito
Score	2–6, 6–3, 6–4

Main article: 2018 Keio Challenger

Yasutaka Uchiyama won the title after defeating Tatsuma Ito 2–6, 6–3, 6–4 in the final.

Seeds

1. Jordan Thompson (semifinals)
2. John Millman (second round, withdrew)
3. Jason Jung (second round)
4. Go Soeda (quarterfinals)
5. Stéphane Robert (quarterfinals)
6. Kwon Soon-woo (first round)
7. Tatsuma Ito (final)
8. Lee Duck-hee (second round)

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	Jordan Thompson	4	5
		Yasutaka Uchiyama	6	7
									Yasutaka Uchiyama	2	6	6
								7	Tatsuma Ito	6	3	4
		Cem İlkel
	7	Tatsuma Ito	w/o

Top half

	First round							Second round							Quarterfinals							Semifinals
	1	J Thompson	2	6	6
		P Gunneswaran	6	4	3			1	J Thompson	6	6
	Q	Hiroyasu Ehara	710	61	6			Q	H Ehara	4	2
		A Whittington	68	77	4										1	J Thompson	6	4	6
	LL	D Nguyen	6	6											5	S Robert	3	6	2
	WC	Yo Watanuki	2	4				LL	D Nguyen	5	0
	Q	Jumpei Yamasaki	6	1	3			5	S Robert	7	6
	5	S Robert	3	6	6																	1	J Thompson	4	5
	4	G Soeda	6	6																			Y Uchiyama	6	7
	WC	Kaito Itsusaki	0	2				4	G Soeda	77	6
		D Wu	6	77					D Wu	65	3
		Ze Zhang	4	65											4	G Soeda	6	60	3
		Y Uchiyama	6	3	6											Y Uchiyama	4	77	6
		H Hurkacz	4	6	4				Y Uchiyama	6	7
	WC	S Hazawa	6	4	77			WC	S Hazawa	3	5
	6	S-w Kwon	3	6	65

Bottom half

	First round							Second round							Quarterfinals							Semifinals
	8	D-h Lee	4	6	6
		T Pütz	6	4	3			8	D-h Lee	2	6	65
	SE	B Ellis	3	4					C İlkel	6	2	77
		C İlkel	6	6												C İlkel	77	6
		M Donati	711	2	5											T Kamke	63	2
		T Kamke	69	6	7				T Kamke	6	6
	Q	Y-s Chung	2	78	4			3	J Jung	4	2
	3	J Jung	6	66	6																		C İlkel
	7	T Ito	6	6																		7	T Ito	w/o
	WC	K Uesugi	2	3				7	T Ito	3	6	77
		J Kubler	6	1	6				J Kubler	6	3	63
		E Leshem	3	6	3										7	T Ito	6	6
		K Kravchuk	0	2											Q	H Moriya	3	3
	Q	H Moriya	6	6				Q	H Moriya	w/o
		M Purcell	3	67				2	J Millman
	2	J Millman	6	79

References

• Main draw
• Qualifying draw