Andy Murray remains optimistic about the ankle injury that threatens to derail his bid to win the Australian Open.

Murray rolled over on his right foot during his second round thrashing of Russian teenager Andrey Rublev, losing balance as he reached for a forehand and tumbling to the floor.

He took treatment from a physio at the next change of ends and later told his box, "my foot is killing me".

Read more: Andy Murray overcomes ankle problem to beat Andrey Rublev in Australian Open second round

However, Murray appeared unhindered as he strolled through the final six games on Rod Laver Arena and sealed a 6-3 6-0 6-2 victory. He will now face American Sam Querrey in round three.

"I don't know how bad it is," Murray said, around 90 minutes after the match had finished.

"Just normally if it's something severe, like a serious ankle injury, you can't put weight on your foot. With ankles, you normally feel a bit worse 20 or 30 minutes after you stop moving around on them.

"It's a little bit stiff just now. It's OK. I don't think I've done too much damage.

"There's not a whole lot you can do apart from icing just now. I'll see in the morning how it feels when I wake up. But hopefully it will be all right."

Murray said his foot had not yet become swollen but admitted he had felt concerned on court.

"I heard a few sort of little crackles and it was sore," Murray said. "It was throbbing kind of for the rest of the match. I was moving fine on it though. It was just sore.

"So you're thinking about it because you have a little bit of pain when you're moving around.

"Also when you're moving into certain positions again on the court, you don't want to do the same movement again. But yeah, I was moving fine towards the end of the match."

Murray is one of few players to wear large ankle supports around both of his feet and the extra solidity could have saved the world number one from further damage.

"Pretty much every player plays with ankle taping or the ankle supports," Murray said.

"I feel like the ankle supports give me a little bit more mobility than the taping but that's just my preference."

Murray walked out on court just as his compatriot Dan Evans was concluding arguably the tournament's biggest shock so far by beating seventh seed Marin Cilic.

The pair's progress means Britain has two men into the Australian third round for the first time since Tim Henman and Greg Rusedski both made it through in 2002. Incidentally, Henman and Rusedski played each other and it was Henman who reached the last 16.

If Kyle Edmund completes a trio by overcoming Spain's 30th seed Pablo Carreno Busta on Thursday, it will be the first time ever that three British players have made it to the third round in Melbourne through a draw of 128 players.

"I saw quite a lot of Dan's match," Murray said.

"I'm really happy for him because he's a nice, nice guy. He's talented. He does work hard. He competes well. Once you get him on the match court, he competes really hard.

"People mature at different ages, they find what's important for them at different ages, too. I think now he's pretty focused on his tennis. With the right people around him, he's doing really well."

Evans will now face Australia's world number 27 Bernard Tomic.