Being on his back for the first time in the octagon and struggling for two or three minutes to get back up, is what gassed Travis out, in my opinion.
I think it's multi-factorial.
Werdum landed very strategic body kicks to the lateral abdomen, which most likely was behind the rib fracture that Browne suffered early during the fight.
Considering how "painful" it can be to inhale fully while having a fractured rib, one can assume that Browne was getting a limited supply of oxygen throughout those 5 rounds.
Werdum, furthermore, laying on top of him and making Browne exhausted only added to Browne's lack of energy.
Leg kicks to the body > Fractured Rib > reduce oxygenation by way of painful inhalation > Browne having to support Werdum's body weight (while Werdum had side control, back and full mount) for extended period = severe exhaustion.
All that taken into account, you have to then realize that Werdum's striking accuracy was on point, which only made matters worse for Browne.
I think Browne will be back and improved in 6-8 months.
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