2003 U.S. Men's Clay Court Championships – Singles

Singles
2003 U.S. Men's Clay Court Championships
2002 Champion	Andy Roddick
Champion	Andre Agassi
Runner-up	Andy Roddick
Score	3–6, 6–3, 6–4
Draw	32
Seeds	8

The 2003 U.S. Men's Clay Court Championships – Singles was an event of the 2003 U.S. Men's Clay Court Championships professional tennis tournament played on outdoor clay courts at the at the Westside Tennis Club in Houston, Texas in the United States and was part of the International Series of the 2003 ATP Tour. The tournament was held from April 21 through April 27, 2006. The singles draw comprised 32 players and eight of them were seeded. Second-seeded Andy Roddick was the defending champion but lost in the final 3–6, 6–3, 6–4 against first-seeded Andre Agassi.

A champion seed is indicated in bold text while text in italics indicates the round in which that seed was eliminated.

Key

	First round							Second round							Quarterfinals							Semifinals							Final
	1	A Agassi	6	6
		Ž Krajan	2	0				1	A Agassi	6	6
		B Vahaly	3	77	3				I Labadze	2	0
		I Labadze	6	62	6										1	A Agassi	6	6
		A Sá	62	0											Q	R Mello	0	1
	Q	R Mello	77	6				Q	R Mello	78	6
		T Martin	6	6					T Martin	66	1
	8	H-T Lee	3	4																		1	A Agassi	6	6
	4	T Dent	6	64	3																		J Melzer	4	1
		J Melzer	4	77	6				J Melzer	5	6	6
	WC	T Blake	65	1					K Carlsen	7	3	4
		K Carlsen	77	6												J Melzer	7	2	7
	Q	S Roitman	3	3												M Fish	5	6	5
		M Fish	6	6					M Fish	6	6
		L Horna	6	6					L Horna	2	4
	6	J-M Gambill	2	4																									1	Andre Agassi	3	6	6
	LL	C Mamiit	3	1																									2	Andy Roddick	6	3	4
		F Saretta	6	6					F Saretta	2	0
		O Mutis	61	6	6				O Mutis	6	6
	WC	H Armando	77	4	1											O Mutis	6	63	6
		A Sávolt	6	6											3	J Blake	4	77	1
		N Kiefer	3	2					A Sávolt	2	62
		A Waske	4	4				3	J Blake	6	77
	3	J Blake	6	6																			O Mutis	6	1	2
	5	V Spadea	6	6																		2	A Roddick	4	6	6
	Q	J Brasington	3	3				5	V Spadea	6	66	3
		J Gimelstob	2	4					F Meligeni	4	78	6
		F Meligeni	6	6												F Meligeni	3	6	4
		T Enqvist	1	67											2	A Roddick	6	4	6
	Q	P Goldstein	6	79				Q	P Goldstein	5	4
	WC	J Morrison	3	1				2	A Roddick	7	6
	2	A Roddick	6	6

• 2003 U.S. Men's Clay Court Championships Draw
• 2003 U.S. Men's Clay Court Championships Qualifying Draw