It'd be very interesting, with the winner getting Martinez at the end. So I would put Daniel Geale in his place for the tourney.
Sergio would have to take some fights in the meantime though, maybe against some legit junior-middelweights, because the tournament would take awhile to end, just like the Super-Six did.
This would be my bracket.
Round 1:
1. Matthew Macklin vs Andy Lee
2. Felix Surm vs Dmitry Pirog
3. Peter Quillin vs Daniel Geale
4. Julio Cesar Chavez Jr vs Hassan N'dam N'Jikam (don't even know who he is lol)
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Round 2:
Winner of fight #1 vs Winner of fight #4
Winner of fight #2 vs Winner of fight #3
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Round 3:
Winner of #1 vs #4 vs #2 vs #3
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Winner of tournament fights Martinez for the lineal title!