Scheduled to compete in the -94kg division and a hot pick as a favorite, Pena took to Facebook to apologize to fans and explain he had an issue with his flight and would not be able to reschedule to arrive in time.
Pena was on track for a third showdown with Xande Ribeiro (view profile), who now looks likely to take gold at the Abu Dhabi Grand Slam, which is streaming live on FloGrappling on Friday, Jan. 13, and Saturday, Jan. 14.
Ribeiro won gold at the Los Angeles Grand Slam, while Pena won in Tokyo and Rio de Janeiro.
Ribeiro is currently in third place in the rankings with 520 points, ahead of Pena who is in fifth with 420 points.
If Pena had won the Grand Slam, worth 200 points, and Ribeiro had taken silver (worth 160), the points would likely be 680 for Ribeiro and 620 for Pena.
With one more Grand Slam (London, March 18) and of course the World Pro in April, this makes things even more interesting to see who could come out on top.
Currently, Gabriel Arges (view profile) leads the rankings race with 840 points. In second place is Jose Junior (view profile), with 770.
The person with the most points at the end of the 2016-17 season will win $25,000. Second place gets $10,000 and third wins $5,000.
The Abu Dhabi Grand Slam goes down on Friday, Jan. 13 (no-gi), and Saturday, Jan. 14 (gi), and you can watch it live or on demand here on FloGrappling.
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