Andy Murray won impressively in straight sets for the second round in a row here at the Australian Open only to find himself upstaged once again by Dan Evans, his fellow countryman. After the world No 1 had secured a place in the fourth round for the ninth year in succession by beating Sam Querrey 6-4, 6-2, 6-4, Evans made the last 16 of a Grand Slam event for the first time in his life by beating Bernard Tomic 7-5, 7-6, 7-6.

Who would have thought just a few days ago that there would be two Britons through to the last 16 of the men’s singles while Novak Djokovic, six times a champion here in the last nine years, was on his way home?

Since the men’s draw at this tournament was expanded to 128 players in 1988, the only previous occasion when two Britons reached the last 16 was when Tim Henman and Greg Rusedski did so in 2001. Both men lost their next matches.

In the fourth round on Sunday Murray will now take on the world No 50, Germany’s Mischa Zverev, who has never gone this far in a Grand Slam tournament, while Evans will meet the world No 12, France’s Jo-Wilfried Tsonga, who was runner-up here in 2008.

It has been a remarkable start to the year for Evans, who will climb to a career-high position in the world’s top 50 at the end of this tournament. The 26-year-old from Birmingham reached his first tour final last week in Sydney, where his victory over Dominic Thiem was his first against a top 10 player, and has gone from strength to strength here.

If Evans’ second-round win over Marin Cilic, the world No 7, was the best of his career, the circumstances of his victory over Tomic made it just as commendable. The 24-year-old Australian was the last home player left in the men’s singles and enjoyed loud support from a passionate crowd in Hisense Arena, which is the third of the show courts at Melbourne Park.

With rain in the air and a stiff breeze blowing on a chilly day by Melbourne’s standards, the conditions were not easy. The match was stopped for five minutes with Evans serving at 5-5 and deuce in the third set, but he held his nerve at what could have been a critical moment.

With his languid style and clever variations of pace, Tomic can be a tricky opponent, but Evans kept his focus throughout. The world No 51, who does not even have a shirt sponsor at the moment, attacked intelligently and played particularly well at the net.

A break of serve at 5-5 helped Evans win the first set, but he was broken when he served for the second at 5-4. His frustration was evident when he was given a warning for an audible obscenity as he served at 5-6, but he held firm and played superbly in the ensuing tie-break, which he won 7-2.

At 4-4 in the third set Evans saved three break points and once again he was much the better player in the tie-break. From 2-1 down he won six of the last seven points to claim victory after two hours and 48 minutes.

Evans is through to his first fourth round match at a grand slam event (Getty)

“It was tough,” Evans said afterwards. “Bernie’s difficult. He’s unorthodox. He plays aggressively and then sometimes slows it down. I found it hard at the start. I’m happy to have come through. It was three tight sets. It could have gone either way.”

Djokovic’s shocking defeat to Denis Istomin on Thursday has left Murray as the clear favourite to win this title for the first time following his five previous defeats in finals, but the Scot’s third-round opponent was a reminder of the potential banana skins ahead. At Wimbledon last summer Querrey produced one of the shocks of the year to beat Djokovic in the third round.

Like Evans, Murray played in Hisense Arena for the first time this year. Querrey, a strapping 6ft 6in American, struck the ball with all his usual power and the match was tight until Murray saved a break point at 3-4 and then broke in the following game after playing three points in a row which encapsulated so many of his finest qualities.

The first demonstrated his brilliant defensive abilities as two superb lobs from difficult positions kept him in the point before Querrey, apparently frustrated at his failure to put his man away, hit a backhand wide. A thumping forehand cross-court return winner took Murray to break point, which he converted with another stunning lob as Querrey attacked the net.

Murray shakes hands with Sam Querrey after their third round encounter (Getty)

In the early stages Murray was still feeling the ankle injury he had sustained in the previous round, but he was soon flying. The Scot took the second set with two breaks of serve, though the third was closer. It turned when Querrey dropped serve at 4-4, having made a horrible volley error to give Murray break point.

“The start of the match was hard,” Murray said afterwards. “Sam came out serving big. He was really going for his shots. The end of that first set was important. He had a break point at 4-3. When I saved that and broke the next game, the momentum was with me. I started to serve a bit better and put a lot more returns back in play after that. I played some good stuff.”

He added: “I think I’ve played a little bit better with each match. I thought I moved much better today than I did in the first two matches, which is really positive for me.”

Asked about his ankle, Murray said: ““It was sore yesterday and a little bit stiff this morning, but it feels good. After the first few games, where I was maybe slightly hesitant, I moved really well towards the end of the first set and in the second and third.”

The Scot’s 48th victory at the Australian Open takes him to joint fourth on the Open era list alongside his coach, Ivan Lendl, and Andre Agassi. Only Roger Federer, Djokovic and Stefan Edberg have won more matches at this event.

Murray said he had been surprised by Djokovic’s defeat given his extraordinary record here, but stressed that the Serb’s results over the last seven months, while moderate by his standards, would be very good by anyone else’s.

Andy Murray celebrates his victory over Sam Querrey after reaching the Australian Open fourth round (Getty)

“He has played some really good stuff over the last six or seven months,” Murray said. “It’s just not been as consistent as what it was the three years before. But it's just unreasonable to expect anyone to keep up that level for their whole career.”

Zverev, Murray’s next opponent, beat Tunisia’s Malek Jaziri 6-1, 4-6, 6-3, 6-0. The world No 50 has been overshadowed in recent times by his hugely talented younger brother, Alexander, who meets Rafael Nadal in the third round tomorrow, but has been in excellent form of late.