Australia has qualified second fastest in tomorrow’s men’s 4x200m freestyle relay final, but star Mack Horton may be the unlucky man to miss out come the medal swim.

The team finished behind Great Britain in the second heat on Tuesday night but in front of powerhouses the USA.

Broome’s Zac Inerti, who anchored the team, said he was determined to qualify faster than the USA.

“I knew the Yanks were hot on our tails so I just tried to hold them off as fast as I can,” he said post-swim.

Italian claimed the first heat, to qualify in third behind Australia.

While the team will prepare for tomorrow’s final, for Horton it may be a case of so close, yet so far.

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Horton swum the slowest split for the relay and admitted he didn’t expect to swim in the final.

“Probably not as good as I was hoping,” Horton

“Probably not good enough to get through to the final team, which is heartbreaking.”

In the other events, Aussie Izaac Stubblety-Cook qualified for the 200m breaststroke semifinals after giving Netherlands swimmer Arno Kamminga a huge start.

The number one ranked swimmer reined in Kamminga to touch the wall for a dead heat in a time of 2.07.37 minutes.

Remarkably there’s been five dead heats already this Olympics.

Stubblety-Cook said he was pleased with the swim, especially the second 100m.

“I was pretty pleased with the second 100m,” he said. “The first 100 was a little touch and go from where I wanted to be.

“It was great to have Kamminga there. It was great to be dragged out with him.”

Matthew Wilson made hard work of his 200m breaststroke heat but his time of 2.09.29 put him in the top 16 fastest swimmers and into the semis.

“That was probably a little harder than I wanted but it’s the first one I’ve done without being fully injured or sick or anything for a long time.,” he said.

“It is good to get that first one out of the way. Hopefully I can keep improving in the semi and hopefully a final the next night. We’ll see.

“If you have a lane, you have a chance.”

Brianna Throssell had a comfortable heat swim after being guaranteed a semifinal berth, easing into third place.

She said she changed her approach to the swim when she knew she was already in the semis.

“Yeah, I guess I was sitting in marshalling ... 16 people in there so provided none of us got disqualified, we were going to make it through, so I wanted to put together a solid swim and not exert myself, just know I can go back to the village and rest and get ready for the semi tomorrow,” Throssell said.

She said she felt a more mature swimmer five years on from Rio.

“I hope I have taken that sort of maturity and experience we need but I still get very nervous and it is the pinnacle of swimming, so the nerves are certainly there,” Throssell said.

Earlier, defending Olympic champion Kyle Chalmers looked strong in his quest for back-to-back golds in the 100m freestyle heats.

Chalmers won heat eight with an impressive time of 47.77 seconds, with reigning world champion Caeleb Dressel just ahead at 47.73 in the final heat, behind Italy’s Thomas Ceccon (47.71).

“What a great way to set this up for the semifinal and the final to come,” Ian Thorpe said on Channel 7.

Unfortunately, Cameron McEvoy failed to qualify for tomorrow’s semifinals, with his time of 48.72 good for 24th.

In the last heat of the night, Aussie Jack McLoughlin qualified for the semi-final of the men’s 800m freestyle, finishing his heat in third.

“I was just trying to keep myself in the mix, I knew I could have a strong last 100, last 50,” he said.

“The goal was just to make it through... it was a bit tighter than I hoped but looking forward to the final now.”

He will now have to wait until Thursday for his next swim.