The final countdown is on.
The Olympic trials have solidified rosters, and with that provided a clearer picture of what and who we'll see when the 2016 Summer Games kick off August 5 in Rio de Janeiro, Brazil.
In some sports, the favorites are clear (coughwomen'sgymnasticscough). In others, the medal field is more open. In the interstitial sweet spot, there are rivalries between countries, and the top podium spot is dangling in the balance.
So what are the best rivalries in Rio? Which teams and individuals are most strongly positioned for a neck-and-neck, winner-take-gold collision?
The stakes and talent don't get any higher, and these are where we could really see sparks fly.