It's business. Before Fedor lost, Strikeforce was looking to have a Fedor-Overeem fight as their first ever PPV event, and wanted to hype it up through a few fights. It's not like their titles have much prestige to lose anyways, with Overeem only having once defended the HW title in years against Rogers.
Fedor only has one fight on his contract, and Strikeforce bent over backwards for Fedor and M1. They might as well cash in on the fight people want to see while they can. If Overeem wins, they'll have two highly ranked HW's that beat the mighty Fedor, and can better sell a Werdum/Overeem fight.

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