Table:
0
A
B
C
D
E
F
1
Outcome
Date
Tournament
Surface
Partner
Opponents in the final
2
Runner-up
1968
Barcelona , Spain
Clay
José Mandarino
Carlos Fernández Patricio Rodríguez
3
Runner-up
1969
London/Queen's Club , U.K.
Grass
Ove Nils Bengtson
Owen Davidson Dennis Ralston
4
Runner-up
1971
Salisbury , U.S.
Carpet
Clark Graebner
Juan Gisbert, Sr. Manuel Orantes
5
Winner
1971
Macon , U.S.
Hard
Clark Graebner
Željko Franulović Jan Kodeš
6
Runner-up
1971
Hampton , U.S.
Hard (i)
Clark Graebner
Ilie Năstase Ion Țiriac
7
Winner
1971
Caracas , Venezuela
Clay
Edison Mandarino
Gerald Battrick Peter Curtis
8
Runner-up
1972
Washington, D.C. , U.S.
Carpet
Clark Graebner
Tom Edlefsen Cliff Richey
9
Runner-up
1974
Gstaad , Switzerland
Clay
Roy Emerson
José Higueras Manuel Orantes
10
Winner
1975
Istanbul , Turkey
Outdoor
Colin Dibley
Colin Dowdeswell John Feaver
11
Runner-up
1982
Itaparica , Brazil
Carpet
Jose Schmidt
Givaldo Barbosa João Soares
12
Runner-up
1983
Bahia , Brazil
Hard
Ricardo Cano
Givaldo Barbosa João Soares

Questions and formulas:
Question: Tell me the opponents for runner-up and surface of grass
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:F1,(A1="runner-up")*(D1="grass")),6))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:F12,(A2:A12="runner-up")*(D2:D12="grass")),6))
Level: medium