Sox Fan,
I am thinking of two of them, one is a little fuzzy. To me the number one catch in Fenway Park was Dewey taking a Homer away from Joe Morgan by reaching into the bullpen during the 1975 World Series.
The other one and I am fuzzy on who or when it occurred was a diving catch Fred Lynn made when he planted his face in the Center Field lawn while running full speed toward home plate.
I am happy for Coco and the Sox and it was a big play given their streak, but for sheer value I will take Dewey's catch. It is hard to top one in the World Series.
I never saw the one you allude to, but that had to be a spectaculer catch.