Dominic Thiem will be haunted—and ultimately strengthened—by losing a dramatic Australian Open final, says Toni Nadal

The fifth-seeded Thiem built a two-sets-to-one lead over defending champion Novak Djokovic before the 32-year-old Serbian fought back for a 6-4, 4-6, 2-6, 6-3, 6-4 triumph to improve to a perfect 8-0 in Melbourne finals and surpass rival Rafael Nadal to regain the world No. 1 ranking.

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Writing for Spanish publication El Pais, Toni Nadal said Thiem's mistake was a slight fourth-set dip in intensity that Djokovic exploited to force a fifth set.

"This mistake will haunt Dominic for a few weeks, preventing him from enjoying the great tournament he has played," Toni Nadal wrote for El Pais. “I think we saw a great game of very high intensity, of incredible level and with points of great beauty. He and Novak are two great fighters who with their performance helped to enhance our sport.

“Surely, this defeat, although painful, will help the Austrian to take another step in his admirable progression.”

Thiem, who toiled four hours, 10 minutes on court toppling Rafael Nadal in the quarterfinals then went three hours, 42 minutes edging Alexander Zverev in the semifinals, went down swinging in a physical four-hour loss to Djokovic that left him feeling completely spent.

Afterward, the Austrian said he has "rarely felt that physically tired" in his career.

Toni Nadal said tactically Thiem played correctly by playing aggressive first strike tennis and backing Djokovic up behind the baseline, but pointed to the fourth set lapse as Thiem "signing his own sentence."

"We saw a fourth set in which Thiem cut his [aggression] back and stopped squeezing the Serbian," Toni Nadal wrote. "He lowered his level of aggressiveness and ceased to be the one who set the pace of the encounter. 

"And, of course, giving Novak the opportunity meant allowing him to recover and thereby signing his own sentence."

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