A booming serve may have been the difference in defending champion Milos Raonic's upset Brisbane International quarter-final win over fifth seed Rafael Nadal on Friday night.
But the world No.3 considered a new zen-like mental state as his biggest weapon after his 4-6 6-3 6-4 victory over the 14-time grand slam winner.
Former Wimbledon finalist Raonic fired down a stunning 23 aces to world No.9 Nadal's four to book a Saturday semi-final with seventh seed Grigor Dimitrov of Bulgaria.
The top-seeded Canadian believed the most lethal part of his arsenal was his new state of mind.
Raonic looked like he was meditating in between games at Pat Rafter Arena as he sat court-side with his eyes closed for extended periods.
"Oh, it's just breathing, to be honest with you, and focusing on what I need to do in that moment," Raonic said.
"(But) I think today the mentality behind the match was what sort of kept me around.
"It's something that I have paid attention to over the last seven months or so.
"That kept me around. That's what I have to be most proud of."
Nadal, 30, may have been ranked lower than top seed Raonic but was the quarter-final favourite after rattling off a total of five wins in the past week in tournaments in Abu Dhabi and Brisbane.
And he looked every bit the man to beat after he broke in the fifth game, taking the first set in 51 minutes.
Raonic hit back in the second, breaking in the eighth game to claim the set in 46 minutes.
He then broke Nadal in the first game of the third set with a booming forehand winner and didn't look back, clinching his first win over Nadal in almost two years.
Nadal - working his way back from knee and wrist injuries - still dominates their head-to-head record 6-2.
Former Wimbledon semi-finalist Dimitrov upset Austrian world No.8 Dominic Thiem 6-3 4-6 6-3 in Friday's quarter-final, outlasting the fourth seed in just over two hours.
In contrast, Japanese world No.5 Kei Nishikori needed just over an hour on Friday to sweep aside the last Australian standing at the tournament - wildcard Jordan Thompson - 6-1 6-1.
Nishikori will face Stan Wawrinka in Saturday's other semi-final after the US Open champion outlasted unseeded Brit Kyle Edmund 6-7 (2-7) 6-4 6-4.
