Olympics-Basketball-Brazil keeps hopes alive with win over Nigeria

* Brazil's fate in Argentine hands * Late run seals win (Adds quotes, detail) By Steve Keating RIO DE JANEIRO, Aug 15 (Reuters) - Brazil beat Nigeria 86-69 on Monday in men's basketball but will have to sit back and watch the remaining Group B contests to see if their efforts are enough to get them into the Olympic medal round. The game may have lacked the electricity of the Brazil-Argentina clash two days earlier but none of the importance with any hope of qualifying for the knockout phase hanging on victory. Brazil (2-3) must now wait for the outcome of the other group matches between Spain and Argentina and Lithuania and Croatia later on Monday before learning their fate. Brazil's bitter sporting rival Argentina must beat Spain if the hosts are to advance. However, Brazil captain Marcelinho Huertas cannot bring himself to cheer for Argentina, who put them on the brink of elimination with a tense 111-107 in double overtime win on Saturday. "We will cheer for Spain to lose," said Huertas. "Of course I will watch it, I'm a basketball addict I am going to be there cheering." Earlier, trailing by 11 at the half, Nigeria battled back to cut the Brazil advantage to 59-54 early in the final quarter, leaving the capacity crowd at the Carioca 1 Arena on the edge of their seats. But the hosts calmed nerves with a 16-5 run to retake control 75-59, exiting the court to a thundering ovation. (Editing by Nina Chestney)