It'd be fair to say that Conor Murray did not see this coming. The yelp as Felix Jones wraps his legs about the Munster scrum-half's neck says it all.
It's possible that he underestimated his adversary's wrestling ability. Maybe the fullback was playing possom. Either way, Jones went from a submissive position to a completely dominant one in an instant.
And whoever was filming the two really enjoyed the move.