#3 The Young Bucks vs The Hardy Boyz
The colossal mistake Impact Wrestling made in the 2010s was not realising the value Matt and Nick Jackson offered to the company. After impressing at Pro Wrestling Guerrilla(PWG), the duo started appearing for ROH, Dragon Gate, Chikara as well as TNA in 2009.
Going by the names of Max and Jeremy Buck and dubbed 'Generation Me' in TNA, the youngsters impressed TNA management during a tryout match against Chris Sabin and Alex Shelley and were offered contracts.
GenMe were put into a feud with Shelley and Sabin but in another case of short-sightedness, the company decided to split them up within three months of their debut - with the Bucks competing for the X-Division Championship.
During their 2009-11 run in TNA, the Bucks never competed against either the Dudley Boyz or the Hardy Boyz - who were also in TNA at the time. While the Bucks did compete against the Dudleys during a shortlived return to the company in 2013, but we never got to see the Hardys taking on the Bucks on TNA TV.
They did have matches for the ROH Tag belts, though just before the Hardys agreed to return to the WWE.