I don't think there is any direct way of doing this with a regex as there is no way to do a capture of the encompassed string without advancing the position.

Thus, you have to reset the position (pos) to the end of the first bracketing word ($+[1]) after each match.

$s = 'The quick brown fox jumped over the other quick brown fox';

print $2 and pos($s) = $+[1] 
    while $s =~ m[\b(\S+)\b(.+?)\b\1\b]g;

 brown fox jumped over the other
 fox jumped over the other quick
 jumped over the other quick brown
[download]

this includes the white space either end of the encompassed text. To avoid that change the regex to  m[\b(\S+)\b\s+(.+?)\s+\b\1\b]g.