Summer McIntosh is staring down another world record — but will she go for it?

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We know now that world records can fall at the swimming world championships in Singapore.

French superstar Leon Marchand crushed the men’s 200-metre individual medley mark during Wednesday’s semifinals at WCH Arena, lowering American Ryan Lochte’s 1:54-flat record all the way to 1:52.69.

It was the first world record to fall at this meet, and it leaves us wondering just how fast the four-time Olympic champion might go in Thursday’s final.

There was some thought, too, that Canada’s Summer McIntosh might aim for a longstanding world record (and the $30,000 US that comes with it) of her own in today’s 200 butterfly semifinal. Instead, she turned on autopilot, cruising to victory in her heat at a relatively slow 2:06.22 — about four seconds off the Canadian-record pace she set at national trials in June. Watch the full semi here.

McIntosh will compete for her third gold medal of the meet in the 200 fly on Thursday at 7:02 a.m. ET, with live coverage on CBCSports.ca and CBC Gem.

As is often the case with the three-time Olympic champion, the question for McIntosh is as much about whether she can win the race as it is about if she can crack the world record in the process.

The mark, which is currently held by China’s Liu Zige at 2:01.81, was set under somewhat strange circumstances in 2009 as Liu took nearly two full seconds off the previous mark while wearing the infamous Speedo LZR Racer, a performance-enhancing supersuit that was already banned in the U.S., and whose worldwide ban was set to take effect three months after Liu’s race.

That confluence of events means Liu’s record has felt nearly untouchable for the past 16 years — it is, in fact, the oldest women’s swimming world record.

WATCH | McIntosh wins 400m freestyle, opening drive for 5 golds with a win:

Summer McIntosh wins world title in 400m freestyle

In June, however, McIntosh threatened Liu’s mark with the second-fastest time ever of 2:02.26. And then she said she had more left to give.

“I think my last stroke was just a little bit wonky, so I think I have at least point-one, point-two in that alone. I can definitely find the other little bits and pieces throughout the race,” McIntosh told CBC Sports’ Devin Heroux at the time.

“The fact that I’m knocking on the door on that world record is really, really encouraging because that’s the world record that I never thought I would even come close to.”

Everything seemed to line up for McIntosh — who set three other world records at trials and is now pursuing the feat of five individual gold medals achieved only by American superstar Michael Phelps in 2007 — to take two shots at another longstanding mark.

Instead, she let her first chance in the semis float away — an interesting contrast to her future training partner Marchand, who wrecked Lochte’s record minutes later.

“Going into tonight I know I just needed to get into the final and use the least energy possible,” McIntosh said. “I really just did not try the first 100, and then gave a little bit of a kick just to get my head on the wall first.”

Heroux and CBC Sports swimming analyst Brittany MacLean Campbell had a fascinating conversation about McIntosh’s race strategy in the latest episode of The Ready Room, which you can watch here:

WATCH | Will Summer McIntosh go for the 200m fly world record?:

Why didn’t Summer McIntosh push for world record in 200 fly semi? | The Ready Room

One key difference between McIntosh and Marchand: the latter eased off his program at these worlds after what he called a tough post-Olympic year.

McIntosh, on the other hand, is chasing that Phelps mark with a loaded, though still carefully curated, schedule. And she may already be looking ahead to Saturday’s 800 freestyle showdown against another American great in Katie Ledecky, which is likely her biggest challenge in climbing the five-gold mountain.

The Canadian beat Ledecky in the 400 freestyle to begin worlds, but Ledecky fired back with a warning shot in the 1,500 yesterday as she posted an astounding 8:09.95 split at the 800 mark — a time McIntosh has only beaten once in her career (though she did it handily in June at 8:05.07).

The 800 is also a new-ish race for McIntosh. She hasn’t swam it at worlds or the Olympics since 2021, when she was 11th and missed the final in Tokyo. It is possible that everything before that Saturday morning duel (8:17 a.m. ET) is mere preparation for the Canadian.

So what does that mean for the 200 butterfly?

Well, it’s hard to go anything less than 100 per cent in a world-championship final. But McIntosh won Olympic gold in the event last summer at 2:03.03. She pointed to American Regan Smith as her top competitor in the semifinal, and Smith’s personal best is 2:03.84. Australia’s Elizabeth Dekkers, who posted the fastest semi-final time, has a personal best of 2:05.20.

WATCH | McIntosh wins 200m IM at worlds:

McIntosh & Harvey go 1 & 3 in 200m IM, Masse & Ruck make 100m backstroke final | THE READY ROOM

It all means McIntosh probably doesn’t have to threaten Liu’s record to win gold. Then again, it would still be massively risky not to go all out for her third victory of the meet — and when the 18-year-old goes all out, even the oldest record in the sport can be broken.

In other record-breaking news, Canada picked up its fourth medal in the pool — and fifth overall — by taking bronze in the 4×100 mixed medley relay. A team of Russian athletes won gold, while China took silver. Olympic champion U.S. missed out on the final after struggling to the 10th-best time in heats.

The Canadian team of Kylie Masse, Taylor Ruck, Josh Liendo and 17-year-old Oliver Dawson raced to a national-record time of 3:40.90 to earn a somewhat surprising podium appearance, especially considering the absence of relay ace Penny Oleksiak.

Liendo’s blistering butterfly leg of 49.64 seconds lifted the Canadians back into medal contention, and Ruck’s anchoring freestyle (52.94) lap secured their spot on the podium. Watch the full race here.

For Masse, it marked her 16th consecutive major meet with a medal and brought her back into a tie with McIntosh — for the time being — for most world podiums by a Canadian with 10. On the flip side, the bronze marked the first of Dawson’s career.

On deck

* Canada’s Ilya Kharun went out quickly but couldn’t hold on in the men’s 200 butterfly, ultimately finishing fourth. Breakout American star Luca Urlando won gold. Watch the full race here. Kharun, the two-time Olympic bronze medallist, will have one more shot to return home with some hardware when he goes head-to-head against Liendo in the 100 butterfly (semis on Friday at 7:10 a.m. ET; final on Saturday at 7:40 a.m. ET).

* Masse will be back in the pool for the 50 backstroke final alongside Ingrid Wilm on Thursday at 7:56 a.m. ET after the Canadian duo qualified with the fifth- and sixth-best times, respectively, in the semifinals. Masse won gold in the 50 at the 2022 worlds and finished fourth a year later.

How to watch

You can stream live action from the World Aquatics Championships on CBCSports.ca and CBC Gem, with additional weekend coverage on CBC TV. See the full streaming and broadcast schedules for details.

Reporter Devin Heroux is on site in Singapore speaking to Canadians following their races, and will join The Ready Room show live on YouTube every day after finals, with Brittany MacLean Campbell hosting from Toronto. The show will include Canadian highlights, athlete interviews and analysis. The show page can be found here.