Alex de Minaur has demonstrated his heart for a clay court battle with a see-saw, rain-interrupted triumph over dangerous French cavalier Ugo Humbert in the Barcelona Open.
In Turkey, new Australian number one Ajla Tomljanovic reached the Istanbul Tennis Championship round of 16 after a comprehensive 6-1, 6-3 win over her compatriot, Jaimee Fourlis.
But there was less success elsewhere for the Aussies as John Millman was knocked out of the Serbia Open and Storm Sanders fell in Stuttgart.
With the clay court season getting into full swing, Australian number one de Minaur demonstrated encouraging signs for his 2022 campaign on the surface at the Real Club de Tenis Barcelona.
The Sydneysider, ranked number 25 in the world, survived a blistering fightback from his fellow 23-year-old to prevail 6-3, 4-6, 6-3.
De Minaur had beaten the 46th-ranked Humbert in the ATP Cup earlier in the year and looked to be powering to a straight sets triumph when the Frenchman broke for a 4-2 lead in the second set.
However, the flamboyant left-hander then went for broke, winning six straight games to take the second set and open up a 2-0 advantage in the decider.
De Minaur rallied to swing the momentum back in his favour, to take the next five games, only for the rain to intervene just as he was about to serve for the match at 5-3.
The 22-minute delay looked to have unsettled the Australian as he returned to swiftly face a break point, but he got the job done on his first match point, prevailing after nearly two and a quarter hours.
It set up a last-16 meeting for de Minaur with South African world number 40 Lloyd Harris, who earned a notable victory over Spain's Albert Ramos-Vinolas 6-3, 6-4.
Millman misses chance for shot at Djokovic
In Belgrade, hardened by his three-set win over the returning Dominic Thiem on Tuesday, Millman was thrown into the deep end again against local Serbian favourite Miomir Kecmanović, who is 42 places higher in the rankings.
The 32-year-old Queenslander had won their previous encounter on clay though, and was buoyed by the prospect of a possible quarter-final meeting with Djokovic at the 20-time grand slam champion's home Novak Tennis Centre.
However, after a 28-shot rally on the first point showed what sort of endurance battle Millman could expect, his 22-year-old opponent eked out the only break in the opening set.
Kecmanović held firm to take the second set in a tie-break, winning 6-4, 7-6 (7-5) after two and a quarter hours.
Djokovic later had an almighty struggle to tame his Serb colleague Laslo Đere, 2-6, 7-6 (8-6), 7-6 (7-4) in an arm wrestle that lasted almost three and a half hours.
Struggling to find any rhythm in what was just Djokovic's fifth match of the year, the 50th-ranked Đere created break-point opportunities in all four of his rival's service games in the opening set.
Djokovic, coming off rare back-to-back defeats after a surprising loss to Alejandro Davidovich Fokina at the Monte Carlo Masters last week, needed all his famed resolve to hold on to his record of not having lost to a compatriot in 10 years.
Storm Sanders blown away by Emma Raducanu
Queensland's Storm Sanders was comprehensively beaten by British teen sensation Emma Raducanu, 6-1, 6-2 at the Stuttgart Open.
Rockhampton's Sanders had gone to the match with high hopes of earning the biggest win of her career on the back of two victories to qualify for the main draw of the clay court event.
After all, Raducanu was playing her first-ever tour-level match on clay, not that it showed.
Showing once again why she is such a rare talent, the 19-year-old Briton survived early buffeting before blowing away the Australian's challenge.
What was most impressive was how Raducanu was able to think on her feet, changing tactics in the fourth game to throw in a couple of looping "moon balls" to disrupt Sanders' early rhythm.
Showing more variety than the Australian and operating with a different level of power, Raducanu began to make the 185-place gulf in their rankings resemble the chasm it really is as she reeled off her victory in 71 minutes.
"[It] definitely wasn't easy," Raducanu said.
"I feel like there were many long deuce games, so I'm very happy to have battled through against Storm.
"She's played two matches in qualifying and she's a great opponent who's extremely tricky, so I'm just really happy to have somehow found a way to come through those long games and put on a good performance."
Raducanu, who suffered from a blister on her foot when playing for GB at the Billie Jean King Cup in Prague at the weekend, did take a little while to find her rhythm but soon looked at home.
"It has been difficult to transition to clay," she explained.
"Last week I was being taught how to slide on the clay using a medicine ball. To have come this far in the space of a week, I am very happy."
AAP/ABC
