DC Special 7 (April/June 1970) features mostly reprints from the Brave and the Bold issues of Strange Sports Stories, although they are billed as Strangest Sports Stories. The fifth tale in the book is actually from Mystery in Space. This must have been a good selling issue, because two later issues of DC Special would also run Strangest Sports Stories.
The first of these was issue 9 (Oct/Dec 70), which contained four reprints, all from Brave and the Bold.
The last was issue 13 (July/Aug 71). Of the six stories in this issue, only two were from Brave and the Bold, the rest from Strange Adventures and Mystery in Space.
The concept must have remained popular, as in 1973 Strange Sports Stories would finally graduate to its own book, with all new material.