The South Orange Open, formerly known as the Eastern Grass Court Championships, is a defunct Grand Prix affiliated tennis tournament founded in 1970 as the Marlborough Open Championships^[1] and was until 1983. It was held in South Orange, New Jersey in the United States and played on outdoor grass courts from 1970 to 1974, and then played on outdoor clay courts from 1975 to 1983. There were men's and women's singles tournaments as well as men's, women's, and mixed doubles.

Ilie Năstase was the most successful player at the tournament, winning the singles competition three times on two different surfaces and the doubles competition twice with American Jimmy Connors.

Results

Men's singles

Year	Champions	Runners-up	Score
1970	Rod Laver	Bob Carmichael	6–4, 6–2, 6–2
1971	Clark Graebner	Pierre Barthès	6–3, 6–4, 6–4
1972	Ilie Năstase	Manuel Orantes	6–4, 6–4
1973	Colin Dibley	Vijay Amritraj	6–4, 6–7, 6–4
1974	Alex Metreveli	Jimmy Connors	walkover
1975	Ilie Năstase	Bob Hewitt	7–6, 6–1
1976	Ilie Năstase	Roscoe Tanner	6–4, 6–2
1977	Guillermo Vilas	Roscoe Tanner	6–4, 6–1
1978	Guillermo Vilas	José Luis Clerc	6–1, 6–3
1979	John McEnroe	John Lloyd	6–7, 6–4, 6–0
1980	José Luis Clerc	John McEnroe	6–3, 6–2
1981	Shlomo Glickstein	Dick Stockton	6–3, 5–7, 6–4
1982	Yannick Noah	Raúl Ramírez	6–3, 7–6
1983	Brad Drewett	John Alexander	4–6, 6–4, 7–6

Men's doubles

Year	Champions	Runners-up	Score
1970	Patricio Cornejo Jaime Fillol	Andrés Gimeno Rod Laver	6–2, 6–4
1971	Bob Carmichael Tom Leonard	Clark Graebner Erik van Dillen	7–6, 6–7, 6–4
1972	Not held
1973	Jimmy Connors Ilie Năstase	Pancho Gonzales Tom Gorman	6–7, 6–3, 6–2
1974	Brian Gottfried Raúl Ramírez	Anand Amritraj Vijay Amritraj	7–6, 6–7, 7–6
1975	Jimmy Connors Ilie Năstase	Dick Crealy John Lloyd	7–6, 7–5
1976	Fred McNair Marty Riessen	Vitas Gerulaitis Ilie Năstase	7–5, 4–6, 6–2
1977	Colin Dibley Wojciech Fibak	Ion Țiriac Guillermo Vilas	6–1, 7–5
1978	Peter Fleming John McEnroe	Ion Țiriac Guillermo Vilas	6–3, 6–3
1979	Peter Fleming John McEnroe	Fritz Buehning Bruce Nichols	6–1, 6–3
1980	Bill Maze John McEnroe	Fritz Buehning Van Winitsky	7–6, 6–4
1981	Fritz Buehning Andrew Pattison	Shlomo Glickstein David Schneider	6–1, 6–4
1982	Raúl Ramírez Van Winitsky	Jai DiLouie Blaine Willenborg	3–6, 6–4, 6–1
1983	Fritz Buehning Tom Cain	John Lloyd Dick Stockton	6–2, 7–5

Women's singles

(incomplete roll)

Year	Champions	Runners-up	Score
1970	Kerry Melville	Patti Hogan	7–6, 6–4.[2]

Women's doubles

(incomplete roll)

Year	Champions	Runners-up	Score
1970	Rosie Casals Virginia Wade	Gail Chanfreau Francoise Durr	6–3, 6–4.[3]