Number 20 was Gold.
After receiving a bit of criticism following his record-setting 19th medal on Day 4, Michael Phelps put to bed any doubt raised about him being the greatest Olympian ever.
How did he do it? Well, he went head-to-head with Ryan Lochte in the 200M Individual Medley and took down his rival, three-peating in the event after winning it in both 2004 and 2008.
So what now for Michael Phelps? Two more swims left in his Olympic career, starting with 100M Butterfly, where he will look to further cement his iconic legacy.
Mel Stewart, a two-time gold medalist in his own right, is here with the breakdown.
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