PARIS - Concerns that Rafa Nadal's reign as king of Roland Garros might be in jeopardy due to an aching back proved wide of the mark on Monday as the world No. 1 led a Spanish charge into the French Open quarterfinals.
On the day that Spanish King Juan Carlos abdicated his throne, there was no danger of his compatriot doing the same in Paris as the eight-times champion produced a 6-1 6-2 6-1 demolition job on Serbian Dusan Lajovic.
Next up will be fellow Spaniard David Ferrer, who lost last year's final to Nadal but beat his compatriot the last time the duo faced each other across a net.
Ferrer stalled Kevin Anderson's bid to become the first South African man in 47 years to reach the last eight of the claycourt major with a 6-3 6-3 6-7 (5) 6-1 win.
Two other Spaniards were sent packing later in the day, spoiling a potential all-Spain top half of the draw.
Seventh-seeded Andy Murray downed Fernando Verdasco 6-4 7-5 7-6 (3) and No. 23 Gael Monfils beat Guillermo Garcia-Lopez 6-0 6-2 7-5.
Canadians Milos Raonic and Eugenie Bouchard are both in quarterfinal action Tuesday. Raonic, seeded eighth, will take on No. 2 Novak Djokovic of Serbia while 18th-seeded Bouchard will play No. 14 Carla Suarez Navarro of Spain.
Nadal, who said he had to slow down his serve in his previous match after being troubled by back pain, left Lajovic with a sore head and aching joints as he went on a rampage to go 5-0 in the first set before rattling off 17 straight points at the start of the second.
The winners flying off Nadal's racket appeared to leave everyone in such a trance that the umpire even fluffed his lines at one stage - telling the players 'to replay the point' in English before sheepishly repeating the instruction in French - drawing a rare smile from Lajovic.
With enigmatic American pop singer Prince watching from the stands, it did not take 83rd-ranked Lajovic too long to discover why beating Nadal at Roland Garros is one of the hardest riddles to crack.
On the eve of his 28th birthday, a screaming forehand winner allowed Nadal to take his formidable French Open win-loss record to 63-1 and just three wins away from sinking his teeth into the Musketeers' Cup.
More importantly for Nadal, his serve had once again picked up speed on day nine of the tournament and there was no evidence of any discomfort.
"My back can be pretty unpredictable," was all Nadal was willing to say when he was quizzed about the subject.
While Nadal being in the final of the French Open is one of the most predictable sights in tennis - his only blip was in 2009 - Ferrer made it that far for the first time only 12 months ago.
Odds of him repeating that run were boosted by his defeat of Nadal in the quarter-final of the Monte Carlo Masters only weeks ago but as Ferrer knows only too well, beating his celebrated rival on the regular tour is completely different to toppling him in a best-of-five set match on red dirt.
While three of the top five men's seeds are still alive, Romanian Simona Halep remained the only top five woman to reach the last eight with a 6-4 6-3 win over Sloane Stephens, whose exit ended American interest in the singles.
Andrea Petkovic's decision to hold off trading in her tennis racket for a career in journalism paid off as she reached a grand slam quarter-final for the first time in three years with a 1-6 6-2 7-5 win over Dutch qualifier Kiki Bertens.
Hobbled by back, ankle and knee injuries that forced her out of the tour for several months over the past two years, the 27-year-old German considered quitting tennis in 2013 to try her luck as a magazine journalist.
"One year ago... I was very close to quitting... just I didn't like playing anymore. I hated it," Petkovic, whose ranking plummeted to 177 last March, told reporters.
"When I came back from my injuries, my footwork was off, my strokes were bad. My serve was bad. I hated it. That's why I wanted to stop.
"(But) my life and destiny still wants me to play tennis ... and right now the only thing that I care about is tennis.
"I do have a lot of interests besides tennis, but nothing really gets my passion so far. I'm I think at the place where I need to be right now. And now I'm here and it's a nice reward."
But having put that plan on the backburner for now, she will be eager to pen a happier tale this week by reaching her first grand slam semifinal.
She will next face 2012 runner-up Sara Errani, who continued the cull of top 10 players with a 7-6(5) 6-2 win over sixth seed Jelena Jankovic.