With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Andre Agassi is a British tennis player.
text_B: Florent Serra was the defending champion , but was eliminated in the Round Robin competition .. Florent Serra. Florent Serra. Novak Djokovic won the title , defeating Chris Guccione 6 -- 3 , 6 -- 7 -LRB- 6 -- 8 -RRB- , 6 -- 4 in the final .. Novak Djokovic. Novak Djokovic. Chris Guccione. Chris Guccione ( tennis )
not_related.