Summer McIntosh vs. Katie Ledecky: Who will win the 2 biggest showdowns at the swimming worlds?

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Summer McIntosh has an extremely ambitious goal for the upcoming swimming world championships in Singapore.

After winning a Canadian-record three gold medals in four individual events at the Paris Olympics last summer, the 18-year-old phenom now wants to become only the second swimmer in history to win five solo titles at a single long-course world championships. The first was Michael Phelps, who did it in 2007 en route to his iconic eight-gold-medal performance at the Beijing Olympics the following year, which included five individual victories and three relay wins.

"[At the] Olympics, the goal was four golds and I didn't reach that," McIntosh told CBC Sports' Devin Heroux after the Canadian trials in June. "So I was hungry for more."

That's right — before she can even legally order a beer in most provinces, Summer is attempting something that only the greatest swimmer in history has ever achieved. And her chances actually look pretty good after she broke three world records at the trials in Victoria (in the 400m freestyle and the 200m and 400m individual medleys) while coming within a second of two more (in the 200m butterfly and 800m freestyle).

The last swimmer to break three long-course world records at the same meet? Phelps in Beijing. Clearly, Summer is already in rarefied air.

But, in order to match Phelps' record five golds at the world championships, McIntosh will have to defeat another GOAT-level American athlete in not one but two races. That would be Katie Ledecky, the 28-year-old freestyle endurance marvel who owns eight individual Olympic gold medals and 16 individual world titles.

Five of those Olympic