Will depend on how he'd lose; if John Molina came in, and wrecked him in two rounds (in primetime on NBC no less), his career would basically be over (would get pushed down to around where Andre Berto currently is).
If Broner-Molina is a straight shootout, with Molina wearing him down late, Broner proves he's got the heart and ability, but shows that he comes up just short; he gets pushed back a bit, but he'd still be a fringe top-10 junior welterweight, 1-2 fights away from getting his world title opportunity. (With a name as big as his is, while still being in his mid-20s, he'd be prime for a voluntary defense of one of the belts)
If Broner-Molina is a straight shootout, with Molina wearing him down late, Broner proves he's got the heart and ability, but shows that he comes up just short; he gets pushed back a bit, but he'd still be a fringe top-10 junior welterweight, 1-2 fights away from getting his world title opportunity. (With a name as big as his is, while still being in his mid-20s, he'd be prime for a voluntary defense of one of the belts)

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